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How to Solve an Algebraic Expression

Last Updated: September 9, 2024 Fact Checked

This article was co-authored by David Jia . David Jia is an Academic Tutor and the Founder of LA Math Tutoring, a private tutoring company based in Los Angeles, California. With over 10 years of teaching experience, David works with students of all ages and grades in various subjects, as well as college admissions counseling and test preparation for the SAT, ACT, ISEE, and more. After attaining a perfect 800 math score and a 690 English score on the SAT, David was awarded the Dickinson Scholarship from the University of Miami, where he graduated with a Bachelor’s degree in Business Administration. Additionally, David has worked as an instructor for online videos for textbook companies such as Larson Texts, Big Ideas Learning, and Big Ideas Math. There are 10 references cited in this article, which can be found at the bottom of the page. This article has been fact-checked, ensuring the accuracy of any cited facts and confirming the authority of its sources. This article has been viewed 504,515 times.

An algebraic expression is a mathematical phrase that contains numbers and/or variables. Though it cannot be solved because it does not contain an equals sign (=), it can be simplified. You can, however, solve algebraic equations , which contain algebraic expressions separated by an equals sign. If you want to know how to master this mathematical concept, then see Step 1 to get started.

Understanding the Basics

Step 1 Understand the difference between an algebraic expression and an algebraic equation.

  • Algebraic expression : 4x + 2
  • Algebraic equation : 4x + 2 = 100

Step 2 Know how to combine like terms.

  • 3x 2 + 5 + 4x 3 - x 2 + 2x 3 + 9 =
  • 3x 2 - x 2 + 4x 3 + 2x 3 + 5 + 9 =
  • 2x 2 + 6x 3 + 14

Step 3 Know how to factor a number.

  • You can see that each coefficient can be divisible by 3. Just "factor out" the number 3 by dividing each term by 3 to get your simplified equation.
  • 3x/3 + 15/3 = 9x/3 + 30/3 =
  • x + 5 = 3x + 10

Step 4 Know the order of operations.

  • (3 + 5) 2 x 10 + 4
  • First, follow P, the operation in the parentheses:
  • = (8) 2 x 10 + 4
  • Then, follow E, the operation of the exponent:
  • = 64 x 10 + 4
  • Next, do multiplication:
  • And last, do addition:

Step 5 Learn how to isolate a variable.

  • 5x + 15 = 65 =
  • 5x/5 + 15/5 = 65/5 =
  • x + 3 = 13 =

Joseph Meyer

Joseph Meyer

To solve an equation for a variable like "x," you need to manipulate the equation to isolate x. Use techniques like the distributive property, combining like terms, factoring, adding or subtracting the same number, and multiplying or dividing by the same non-zero number to isolate "x" and find the answer.

Solve an Algebraic Equation

Step 1 Solve a basic linear algebraic equation.

  • 4x + 16 = 25 -3x =
  • 4x = 25 -16 - 3x
  • 4x + 3x = 25 -16 =
  • 7x/7 = 9/7 =

Step 2 Solve an algebraic equation with exponents.

  • First, subtract 12 from both sides.
  • 2x 2 + 12 -12 = 44 -12 =
  • Next, divide both sides by 2.
  • 2x 2 /2 = 32/2 =
  • Solve by taking the square root of both sides, since that will turn x 2 into x.
  • √x 2 = √16 =
  • State both answers:x = 4, -4

Step 3 Solve an algebraic expression with fractions.

  • First, cross multiply to get rid of the fraction. You have to multiply the numerator of one fraction by the denominator of the other.
  • (x + 3) x 3 = 2 x 6 =
  • Now, combine like terms. Combine the constant terms, 9 and 12, by subtracting 9 from both sides.
  • 3x + 9 - 9 = 12 - 9 =
  • Isolate the variable, x, by dividing both sides by 3 and you've got your answer.
  • 3x/3 = 3/3 =

Step 4 Solve an algebraic expression with radical signs.

  • First, move everything that isn't under the radical sign to the other side of the equation:
  • √(2x+9) = 5
  • Then, square both sides to remove the radical:
  • (√(2x+9)) 2 = 5 2 =
  • Now, solve the equation as you normally would by combining the constants and isolating the variable:
  • 2x = 25 - 9 =

Step 5 Solve an algebraic expression that contains absolute value.

  • |4x +2| - 6 = 8 =
  • |4x +2| = 8 + 6 =
  • |4x +2| = 14 =
  • 4x + 2 = 14 =
  • Now, solve again by flipping the sign of the term on the other side of the equation after you've isolated the absolute value:
  • 4x + 2 = -14
  • 4x = -14 -2
  • 4x/4 = -16/4 =
  • Now, just state both answers: x = -4, 3

Community Q&A

Donagan

  • The degree of a polynomial is the highest power within the terms. Thanks Helpful 9 Not Helpful 1
  • Once you're done, replace the variable with the answer, and solve the sum to see if it makes sense. If it does, then, congratulations! You just solved an algebraic equation! Thanks Helpful 7 Not Helpful 3
  • To cross-check your answer, visit wolfram-alpha.com. They give the answer and often the two steps. Thanks Helpful 8 Not Helpful 5

problem solving about algebraic expressions

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Evaluate an Algebraic Expression

  • ↑ https://www.math4texas.org/Page/527
  • ↑ https://www.khanacademy.org/math/cc-sixth-grade-math/cc-6th-expressions-and-variables/cc-6th-combining-like-terms/v/combining-like-terms-2
  • ↑ https://www.mathsisfun.com/algebra/factoring.html
  • ↑ https://www.mathsisfun.com/operation-order-pemdas.html
  • ↑ https://sciencing.com/tips-for-solving-algebraic-equations-13712207.html
  • ↑ https://www.mathsisfun.com/algebra/equations-solving.html
  • ↑ https://tutorial.math.lamar.edu/Classes/Alg/SolveExpEqns.aspx
  • ↑ https://www.mathsisfun.com/algebra/fractions-algebra.html
  • ↑ https://math.libretexts.org/Courses/Coastline_College/Math_C045%3A_Beginning_and_Intermediate_Algebra_(Tran)/10%3A_Roots_and_Radicals/10.07%3A_Solve_Radical_Equations
  • ↑ https://www.mathplanet.com/education/algebra-1/linear-inequalitites/solving-absolute-value-equations-and-inequalities

About This Article

David Jia

If you want to solve an algebraic expression, first understand that expressions, unlike equations, are mathematical phrase that can contain numbers and/or variables but cannot be solved. For example, 4x + 2 is an expression. To reduce the expression, combine like terms, for example everything with the same variable. After you've done that, factor numbers by finding the lowest common denominator. Then, use the order of operations, which is known by the acronym PEMDAS, to reduce or solve the problem. To learn how to solve algebraic equations, keep scrolling! Did this summary help you? Yes No

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problem solving about algebraic expressions

Algebraic Expressions and Word Problems

Related Topics: More Lessons for Grade 7 Math Worksheets

Examples, solutions, videos, worksheets, games and activities to help Algebra 1 or grade 7 students learn how to write algebraic expressions from word problems.

Beginning Algebra & Word Problem Steps

  • Name what x is.
  • Define everything in the problem in terms of x.
  • Write the equation.
  • Solve the equation.
  • Kevin’s age is 3 years more than twice Jane’s age. The sum of their ages is 39. How old is Kevin and Jane?
  • The difference between two numbers is 7. Find the two numbers if the larger number is three times the smaller.
  • Mary and Jim collect baseball cards, Mary has 5 more than 3 times as many cards as Jim. The total number of cards they both have is 253. How many cards does Mary have?

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7.3 Simple Algebraic Equations and Word Problems

An algebraic equation is a mathematical sentence expressing equality between two algebraic expressions (or an algebraic expression and a number).

When two expressions are joined by an equal (=) sign, it indicates that the expression to the left of the equal sign is identical in value to the expression to the right of the equal sign.

For example, when two algebraic expressions, such as [latex]5x + 7[/latex] and [latex]x + 19[/latex], are equal, the two expressions are joined by an equal (=) sign and the equation is written as:

[latex]5x + 7 = x + 19[/latex]

‘Left side’ (LS) = ‘Right side’ (RS)

The solution to the equation is the value of the variable that makes the left side (LS) evaluate to the same number as the right side (RS).

Note: You need an equation to solve for an unknown variable – you cannot solve for a variable in an algebraic expression that is not part of an equation.

  • If you have an expression , it needs to be simplified .
  • If you have an equation , it needs to be solved .

In algebra, there are a variety of equations. In this section, we will learn one equation category, linear equations with one variable .

Examples of linear equations with one variable are:

[latex]2x = 8[/latex],   [latex]3x + 5 = 14[/latex],   [latex]5x + 7 = x + 19[/latex]

An equation is either true or false depending on the value of the variable.

For example, consider the equation [latex]2x = 8[/latex]:

  • If [latex]x = 4[/latex],   LS = 2(4) = 8, RS = 8; therefore, the equation is true.
  • If [latex]x = 3[/latex],   LS = 2(3) = 6, RS = 8; therefore, the equation is false.

Equations may be classified into the following three types:

  • Conditional equation: these equations are only true when the variable has a specific value. For example, [latex]2x = 8[/latex] is a conditional equation, true if and only if [latex]x = 4[/latex].
  • Identity: these equations are true for any value for the variable. For example, [latex]2x + 10 = 2(x + 5)[/latex] is an identity, true for any value of [latex]x[/latex].
  • Contradiction: these equations are not true for any value of the variable. For example, [latex]x + 5 = x + 4[/latex] is a contradiction, not true for any value of [latex]x[/latex].

Equivalent Equations

Equations with the same solutions are called equivalent equations .

For example, [latex]2x + 5 = 9[/latex] and [latex]2x = 4[/latex] are equivalent equations because the solution [latex]x = 2[/latex] satisfies each equation.

Similarly, [latex]3x - 4 = 5[/latex], [latex]2x = x + 3[/latex], and [latex]x + 1 = 4[/latex] are equivalent equations because the solution [latex]x = 3[/latex] satisfies each equation.

Properties of Equality

If [latex]a = b[/latex], then,

Properties of Equality with Corresponding Expressions
Expression Property Meaning
[latex]a = b[/latex] Symmetric Property Interchanging LS and RS.
[latex]a + c = b + c[/latex] Addition Property Adding the same quantity to both sides.
[latex]a - c = b - c[/latex] Subtraction Property Subtracting the same quantity from both sides.
[latex]a \cdot c = b \cdot c[/latex] Multiplication Property Multiplying by the same quantity on both sides.
[latex]\displaystyle{\frac{a}{c} = \frac{b}{c}}[/latex] Division Property, [latex]c \neq 0[/latex] Dividing by the same quantity on both sides.

These properties are used to solve equations.

Equations with Fractional Coefficients

If an equation contains fractional coefficients, then the fractional coefficients can be changed to whole numbers by multiplying both sides of the equation by the least common denominator (LCD) of all the fractions, using the Multiplication Property.

For example,

[latex]\displaystyle{\frac{2}{3}x = \frac{5}{2} + 4}[/latex] Since the LCD of the denominators 3 and 2 is 6, multiply both sides of the equation by 6.

[latex]\displaystyle{6\left(\frac{2}{3}x\right) = 6\left(\frac{5}{2} + 4\right)}[/latex] This is the same as multiplying each term by the LCD of 6.

[latex]\displaystyle{6\left(\frac{2}{3}x\right) = 6\left(\frac{5}{2}\right) + 6(4)}[/latex] Simplifying, [latex]4x = 15 + 24[/latex] Now, the equation has only whole number coefficients [latex]4x = 39[/latex].

Equations with Decimal Coefficients

If an equation contains decimal coefficients, then the decimal coefficients can be changed to whole numbers by multiplying both sides of the equation by an appropriate power of 10, using the Multiplication Property.

[latex]\underline{1.25}x = \underline{0.2} + 4[/latex] Since there is at most 2 decimal places in any of the coefficients or constants, multiply both sides of the equation by [latex]10^2 = 100[/latex].

[latex]100(1.25x) = 100(0.2 + 4)[/latex] This is the same as multiplying each term by 100. [latex]100(1.25x) = 100(0.2) + 100(4)[/latex] Simplifying, [latex]125x = 20 + 400[/latex] Now, the equation has only whole number coefficients [latex]125x = 420[/latex].

Steps to Solve Algebraic Equations with One Variable

If the equation contains fraction and/or decimal coefficients, it is possible to work with them as they are – in that case, proceed to Step 2. Alternatively, as explained earlier, the equation may be rewritten in whole numbers to make calculations and rearrangements easier.

If present, expand and clear brackets in the equation by following the order of arithmetic operations (BEDMAS).

Use the addition and subtraction properties to collect and group all variable terms on the left side of the equation and all constants on the right side . Then, simplify both sides.

Note: If it is more convenient to gather all the variable terms on the right side and the constants on the left side, you may do so, and then use the symmetric property and switch the sides of the equation to bring the variables over to the left side and the constants to the right side.

Use the division and multiplication properties to ensure that the coefficient of the variable is +1.

After completing Step 4, there should be a single variable with a coefficient of +1 on the left side and a single constant term on the right side – that constant term is the solution to the equation.

Verify the answer by substituting the solution from Step 5 back into the original problem.

State the answer.

Example 7.3-a: Solving Equations Using the Addition and Subtraction Properties

Solve the following equations and verify the solutions:

  • [latex]x - 11 = 4[/latex]
  • [latex]8 + x = 20[/latex]
  • [latex]x - 11 = 4[/latex] Adding 11 to both sides, [latex]x - 11 + 11 = 4 + 11[/latex] [latex]x = 15[/latex] Verify by substituting [latex]x = 15[/latex]: LS [latex]= x - 11 = 15 - 11 = 4[/latex]     RS [latex]= 4[/latex] LS = RS Therefore, the solution is [latex]x = 15[/latex].
  • [latex]8 + x = 20[/latex] Subtracting 8 from both sides, [latex]8 - 8 + x = 20 - 8[/latex] [latex]x = 12[/latex] Verify by substituting [latex]x = 12[/latex]: LS [latex]= 8 + x = 8 + 12 = 20[/latex]   RS [latex]= 20[/latex] LS = RS Therefore, the solution is [latex]x = 12[/latex].

Example 7.3-b: Solving Equations Using the Multiplication and Division Properties

  • [latex]5x = 20[/latex]
  • [latex]\displaystyle{\frac{3}{8}x = 12}[/latex]
  • [latex]5x = 20[/latex] Dividing both sides by 5 , [latex]\displaystyle{\frac{5x}{5} = \frac{20}{5}}[/latex] [latex]x = 4[/latex] Verify by substituting [latex]x = 4[/latex]: LS [latex]= 5x = 5(4) = 20[/latex]   RS [latex]= 20[/latex] LS = RS Therefore, the solution is [latex]x = 4[/latex].
  • [latex]\displaystyle{\frac{3}{8}x = 12}[/latex] Multiplying both sides by [latex]\displaystyle{\frac{8}{3}}[/latex] (the reciprocal of [latex]\displaystyle{\frac{3}{8}}[/latex]), [latex]\displaystyle{\left(\frac{8}{3}\right) \cdot \frac{3}{8}x = \left(\frac{8}{3}\right) \cdot 12}[/latex] [latex]x = 8 \times 4[/latex] [latex]x = 32[/latex]   or  [latex]\displaystyle{\frac{3}{8}x = 12}[/latex] Multiplying both sides by 5 , [latex]\displaystyle{(8) \cdot \frac{3}{8}x = (8) \cdot 12}[/latex] [latex]3x = 96[/latex]Dividing both sides by 3 , [latex]\displaystyle{\frac{3x}{3} = \cdot \frac{96}{3}}[/latex][latex]x = 32[/latex]Verify by substituting [latex]x = 32[/latex]:LS [latex]\displaystyle{= \frac{3}{8}x = \frac{3}{8} \times 32 = 12}[/latex]RS [latex]= 12[/latex]LS = RSTherefore, the solution is [latex]x = 32[/latex].

Example 7.3-c: Solving Equations with Variables on Both Sides

  • [latex]3x - 8 = 12 - 2x[/latex]
  • [latex]15 + 6x - 4 = 3x + 31 - x[/latex]
  • [latex]3x - 8 = 12 - 2x[/latex] Adding 2x to both sides,[latex]3x + 2x - 8 = 12 - 2x + 2x[/latex] [latex]5x - 8 = 12[/latex] Adding 8 to both sides,[latex]5x - 8 + 8 = 12 + 8[/latex] [latex]5x = 20[/latex] Dividing both sides by 5 , [latex]\displaystyle{\frac{5x}{5} = \frac{20}{5}}[/latex] [latex]x = 4[/latex] Verify by substituting [latex]x = 4[/latex]: LS [latex]= 3x - 8 = 3(4) - 8 = 12 - 8 = 4[/latex]RS [latex]= 12 - 2x = 12 - 2(4) = 12 - 8 = 4[/latex]LS = RSTherefore, the solution is [latex]x = 4[/latex].
  • [latex]15 + 6x - 4 = 3x + 31 - x[/latex] Combining like terms (LS: [latex]15 - 4 = 11[/latex], and RS: [latex]3x - x = 2x[/latex]), [latex]11 + 6x = 2x + 31[/latex]   Subtracting [latex]2x[/latex] from both sides, [latex]11 + 6x - 2x = 2x - 2x + 31[/latex] [latex]11 + 4x = 31[/latex] Subtracting 11 from both sides, [latex]11 - 11 + 4x = 31 - 11[/latex] [latex]4x = 20[/latex] Dividing both sides by 4 , [latex]\displaystyle{\frac{4x}{4} = \frac{20}{4}}[/latex] [latex]x = 5[/latex] Verify by substituting [latex]x = 5[/latex] back into the original equation:LS [latex]= 15 + 6x - 4 = 15 + 6(5) - 4 = 15 + 30 - 4 = 41[/latex]RS [latex]= 3x + 31 - x = 3(5) + 31 - 5 = 15 + 31 - 5 = 41[/latex]LS = RSTherefore, the solution is [latex]x = 5[/latex].

Example 7.3-d: Solving Equations with Fractions

Solve the following equation and verify the solution:

[latex]\displaystyle{\frac{x}{3} - \frac{1}{12} = \frac{1}{6} + \frac{x}{4}}[/latex]

[latex]\displaystyle{\frac{x}{3} - \frac{1}{12} = \frac{1}{6} + \frac{x}{4}}[/latex] LCD of 3, 4, 6, and 12 is 12.

Multiplying each term by 12 ,

[latex]\displaystyle{12\left(\frac{x}{3}\right) - 12\left(\frac{1}{12}\right) = 12\left(\frac{1}{6}\right) + 12\left(\frac{x}{4}\right)}[/latex]

[latex]4x - 1 = 2 + 3x[/latex]

Subtracting [latex]3x[/latex] from both sides,

[latex]4x - 3x - 1 = 2 + 3x - 3x[/latex]

[latex]x - 1 = 2[/latex]

Adding 1 to both sides,

[latex]x - 1 + 1 = 2 + 1[/latex]

[latex]x = 3[/latex]

Verify by substituting [latex]x = 3[/latex] back into the original equation:

LS [latex]\displaystyle{= \frac{x}{3} - \frac{1}{12} = \frac{3}{3} - \frac{1}{12} = \frac{12}{12} - \frac{1}{12} = \frac{11}{12}}[/latex]

RS [latex]\displaystyle{= \frac{1}{6} + \frac{x}{4} = \frac{1}{6} + \frac{3}{4} = \frac{2}{12} + \frac{9}{12} = \frac{11}{12}}[/latex]

Therefore, the solution is [latex]x = 3[/latex].

Example 7.3-e: Solving Equations with Decimals

[latex]0.15x + 1.2 = 0.4x - 0.8[/latex]

[latex]0.15x + 1.2 = 0.4x - 0.8[/latex] Greatest number of decimal places is 2 (i.e., hundredths).

Multiplying all the terms by [latex]10^2 = 100[/latex],

[latex]100(0.15x) + 100(1.2) = 100(0.4x) - 100(0.8)[/latex]

[latex]15x + 120 = 40x - 80[/latex]

Interchanging the LS and RS using the Symmetric Property to have the larger x term on the LS,

[latex]40x - 80 = 15x + 120[/latex]

Subtracting [latex]15x[/latex] from both sides,

[latex]40x - 15x - 80 = 15x - 15x + 120[/latex]

[latex]25x - 80 = 120[/latex]

Adding 80 to both sides,

[latex]25x - 80 + 80 = 120 + 80[/latex]

[latex]25x = 200[/latex]

Dividing both sides by 25 ,

[latex]\displaystyle{\frac{25x}{25} = \frac{200}{25}}[/latex]

[latex]x = 8[/latex]

Verify by substituting [latex]x = 8[/latex] back into the original equation:

LS [latex]= 0.15x + 1.2 = 0.15(8) + 1.2 = 1.2 + 1.2 = 2.4[/latex]

RS [latex]= 0.4x - 0.8 = 0.4(8) - 0.8 = 3.2 - 0.8 = 2.4[/latex]

Therefore, the solution is [latex]x = 8[/latex].

Note: For the rest of the examples in this section, we will not show the verification by substitution step.

Example 7.3-f: Solving Equations Using All the Properties

Solve the following equations by using the properties of equality, and express the answer as a fraction in its lowest terms, or as a mixed number, wherever applicable:

  • [latex]8x + 7 - 3x = -6x - 15 + x[/latex]
  • [latex]2(3x - 7) = 28 - 3(x + 1)[/latex]
  • [latex]\displaystyle{\frac{1}{4}(x + \frac{2}{3}) = \frac{1}{2}(x - 3) + x}[/latex]
  • [latex]0.45(2x + 3) - 2.55 = 0.6(3x - 5)[/latex]
  • [latex]\displaystyle{\frac{x + 2}{3} = \frac{5 - 2x}{7}}[/latex]
  • [latex]8x + 7 - 3x = -6x - 15 + x[/latex] Grouping like terms on both sides, [latex]8x - 3x + 7 = -6x + x - 15[/latex] [latex]5x + 7 = -5x - 15[/latex] Adding 5 to both sides, [latex]5x + 5x + 7 = -5x + 5x - 15[/latex] [latex]10x + 7 = -15[/latex] Subtracting 7 from both sides, [latex]10x + 7 - 7 = -15 - 7[/latex] [latex]10x = -22[/latex] Dividing both sides by 10 , [latex]\displaystyle{\frac{10x}{10} = -\frac{22}{10}}[/latex] [latex]\displaystyle{x = -\frac{11}{5} = -2\frac{1}{5}}[/latex]
  • [latex]2(3x - 7) = 28 - 3(x + 1)[/latex] Expanding both sides,[latex]6x - 14 = 28 - 3x - 3[/latex]   Grouping like terms,[latex]6x - 14 = 28 - 3 - 3x[/latex] [latex]6x - 14 = 25 - 3x[/latex] Adding [latex]3x[/latex] to both sides,[latex]6x + 3x - 14 = 25 - 3x + 3x[/latex] [latex]9x - 14 = 25[/latex] Adding 14 to both sides, [latex]9x - 14 + 14 = 25 + 14[/latex] [latex]9x = 39[/latex] Dividing both sides by 9 ,[latex]\displaystyle{\frac{9x}{9} = \frac{39}{9}}[/latex] [latex]\displaystyle{x = \frac{13}{3} = 4\frac{1}{3}}[/latex]
  • [latex]\displaystyle{\frac{1}{4}(x + \frac{2}{3}) = \frac{1}{2}(x - 3) + x}[/latex] Expanding both sides, [latex]\displaystyle{\frac{1}{4}x + \frac{1}{6} = \frac{1}{2}x - \frac{3}{2} + x}[/latex] Multiplying each term by the LCD 12 , [latex]\displaystyle{12\left(\frac{1}{4}x\right) + 12\left(\frac{1}{6}\right) = 12\left(\frac{1}{2}x\right) - 12\left(\frac{3}{2}\right) + 12(x)}[/latex] [latex]3x + 2 = 6x - 18 + 12x[/latex] Grouping like terms,[latex]3x + 2 = 6x + 12x - 18[/latex] [latex]3x + 2 = 18x - 18[/latex] Interchanging the LS and RS using the Symmetric Property to have the larger x term on the LS, [latex]18x 18 = 3x + 2[/latex]   Subtracting [latex]3x[/latex] from both sides, [latex]18x - 3x - 18 = 3x - 3x + 2[/latex] [latex]15x - 18 = 2[/latex] Adding 18 to both sides, [latex]15x - 18 + 18 = 2 + 18[/latex] [latex]15x = 20[/latex] Dividing both sides by 15 , [latex]\displaystyle{\frac{15x}{15} = \frac{20}{15}}[/latex][latex]\displaystyle{x = \frac{4}{3} = 1\frac{1}{3}}[/latex]
  • [latex]0.45(2x + 3) - 2.55 = 0.6(3x - 5)[/latex] Expanding both sides, [latex]0.90x + 1.35 - 2.55 = 1.8x - 3.0[/latex] Greatest number of decimal places is 2 (i.e., hundredths). Multiplying all the terms by [latex]10^2 = 100[/latex],   [latex]100(0.90x) + 100(1.35) - 100(2.55) = 100(1.8x) - 100(3.0)[/latex] [latex]90x + 135 - 255 = 180x - 300[/latex] Grouping like terms,[latex]90x 120 = 180x 300[/latex] Interchanging the LS and RS using the Symmetric Property to have the larger x term on the LS,   [latex]180x - 300 = 90x - 120[/latex] Subtracting [latex]90x[/latex] from both sides,  [latex]180x - 90x - 300 = 90x - 90x - 120[/latex] [latex]90x - 300 = -120[/latex] Adding 300 to both sides,  [latex]90x - 300 + 300 = -120 + 300[/latex] [latex]90x = 180[/latex] Dividing both sides by 90 ,  [latex]\displaystyle{\frac{90x}{90} = \frac{180}{90}}[/latex] [latex]x = 2[/latex]
  • [latex]\displaystyle{\frac{x + 2}{3} = \frac{5 - 2x}{7}}[/latex] Cross-multiplying,  [latex]7(x + 2) = 3(5 - 2x)[/latex] Expanding both sides,[latex]7x + 14 = 15 - 6x[/latex] Adding [latex]6x[/latex] to both sides,  [latex]7x + 6x + 14 = 15 - 6x + 6x[/latex] [latex]13x + 14 = 15[/latex] Subtracting 14 from both sides, [latex]13x + 14 - 14 = 15 - 14[/latex] [latex]13x = 1[/latex] Dividing both sides by 13 ,  [latex]\displaystyle{\frac{13x}{13} = \frac{1}{13}}[/latex] [latex]\displaystyle{x = \frac{1}{13}}[/latex]

Steps to Solve Word Problems

Read the entire problem and ensure you understand the situation.

Identify the given information and the question to be answered.

Look for keywords. Some words indicate certain mathematical operations (see Table 7.1).

Choose a variable to represent the unknown(s) and state what that variable represents, including the unit of measure.

Note: For now, if there is more than one unknown, try to identify all the unknowns in terms of one variable, as all the questions in this chapter can be solved with only one variable.

Where necessary, draw a simple sketch to identify the information. This helps with envisioning the question more clearly.

Create an equation (or set of equations) to describe the relationship between the variables and the constants in the question.

Group like terms, isolate the variable and solve for the unknown(s).

State the solution to the given problem.

Example 7.3-g: Solving a Word Problem Using Algebraic Equations

If Harry will be 65 years old in 5 years, how old is he today?

Let Harry’s age today be x years.

Therefore, in 5 years, Harry’s age will be:

[latex]x + 5 = 65[/latex]   Solving for [latex]x[/latex],

[latex]x = 65 - 5 = 60[/latex]

Therefore, Harry is 60 years old today.

Example 7.3-h: Solving a Geometry Problem Using Algebraic Equations

The perimeter of a rectangular garden is 50 metres. The length is 5 metres more than the width. Find the dimensions of the garden.

Hint: Perimeter = 2(length) + 2(width)

Let the width be [latex]w[/latex] metres.

Therefore, the length is (w + 5) metres.

Perimeter = 2(length) + 2(width)

[latex]50 = 2(w + 5) + 2w[/latex]

[latex]50 = 2w + 10 + 2w[/latex]

[latex]2w + 10 + 2w = 50[/latex]

[latex]4w + 10 = 50[/latex]

[latex]4w = 50 - 10[/latex]

[latex]4w = 40[/latex]

[latex]\displaystyle{w = \frac{40}{4}}[/latex]

[latex]w = 10[/latex]

Therefore, the width of the garden is 10 metres and the length is (10 + 5) = 15 metres.

Example 7.3-i: Solving a Finance Problem Using Algebraic Equations

A TV costs $190 more than a Blu-ray player. The total cost of the TV and the Blu-ray player is $688. Calculate the cost of the TV and the cost of the Blu-ray player.

Let the cost of the Blu-ray player be [latex]\$x[/latex].

Therefore, the cost of the TV is [latex]\$(x + 190.00)[/latex].

The total cost is $688.00.

[latex]x + (x + 190.00) = 688.00[/latex]

[latex]x + x + 190.00 = 688.00[/latex]

[latex]2x + 190.00 = 688.00[/latex]

[latex]2x = 688.00 - 190.00[/latex]

[latex]2x = 498.00[/latex]

[latex]\displaystyle{x = \frac{498.00}{2}}[/latex]

[latex]x = \$249.00[/latex]

Therefore, the cost of the Blu-ray player is $249.00 and the cost of the TV is (249.00 + 190.00) = $439.00.

Example 7.3-j: Solving a Mixture Problem Using Algebraic Equations

How many litres of water need to be added to 30 litres of a 15% saline solution to make a saline solution that is 10% saline?

Example 7.3-j Solution Table
Solution Ingredients # of Litres % Saline Total Litres of Saline
Water [latex]x[/latex] [latex]0[/latex] [latex]0[/latex]
15% Saline Solution [latex]30[/latex] [latex]0.15[/latex] [latex]0.15 \times 30 = 4.5[/latex]
10% Saline Solution [latex]30 + x[/latex] [latex]0.10[/latex] [latex]0.10 \times (30 + x)[/latex]

From the last column, we get the equation for the saline mix. The number of litres of saline in the 15% solution must be the same as the number of litres in the final 10% solution, as only water is being added, which does not contribute any additional saline to the solution. Therefore,

[latex]4.5 = 0.10 \times (30 + x)[/latex]

[latex]4.5 = 3 + 0.10x[/latex]

[latex]1.5 = 0.10x[/latex]

[latex]x = 15[/latex]

Therefore, 15 litres of water need to be added to the 15% saline solution to make the solution 10% saline.

7.3 Exercises

Answers to the odd-numbered problems are available at the end of the textbook .

For problems 1 to 8, simplify and evaluate the expressions.

  • The sum of a number and six is ten.
  • A number decreased by fifteen is five.
  • Six times a number is seventy-two.
  • The product of a number and four is twenty-eight.
  • A number divided by five is four.
  • A number divided by three is three.
  • Two-thirds of a number is twelve.
  • Two-fifths of a number is six.

For problems 9 to 30, solve the algebraic equations using the properties of equality, and express the answer as a fraction in its lowest terms or as a mixed number, wherever applicable.

  • [latex]x - 20 = 10[/latex]
  • [latex]x - 25 = 17[/latex]
  • [latex]22 = 40 - x[/latex]
  • [latex]54 = 23 - x[/latex]
  • [latex]21 + x = 4[/latex]
  • [latex]50 + x = 45[/latex]
  • [latex]16 + x = 22[/latex]
  • [latex]12 + x = 38[/latex]
  • [latex]11x + 4 = 17[/latex]
  • [latex]7x - 16 = 22[/latex]
  • [latex]\displaystyle{x - \frac{4}{5} = \frac{3}{5}}[/latex]
  • [latex]\displaystyle{x - \frac{1}{6} = 1}[/latex]
  • [latex]\displaystyle{\frac{10}{15} = x - \frac{4}{3}}[/latex]
  • [latex]\displaystyle{\frac{x}{7} + 15 = 24}[/latex]
  • [latex]\displaystyle{x + \frac{2}{5} = \frac{1}{4}}[/latex]
  • [latex]\displaystyle{2x - \frac{2}{3} = \frac{5}{6}}[/latex]
  • [latex]4x = 24[/latex]
  • [latex]\displaystyle{\frac{2x}{3} + 1 = \frac{5x}{8} + 2}[/latex]
  • [latex]\displaystyle{\frac{x}{2} - \frac{1}{6} = \frac{1}{3} + \frac{3x}{5}}[/latex]
  • [latex]\displaystyle{\frac{7x}{8} - 4 = \frac{x}{4} + 6}[/latex]
  • [latex]\displaystyle{\frac{8x}{3} - 5 = \frac{x}{3} + 2}[/latex]

For problems 31 to 54, solve the algebraic equations using the properties of equality, and round the answer to 2 decimal places, wherever applicable.

  • [latex]10y - 0.09y = 17[/latex]
  • [latex]x + 0.13x = 70[/latex]
  • [latex]0.3x - 3.2 = 0.4 - 0.6x[/latex]
  • [latex]4 + 0.2x = 0.7x - 0.5[/latex]
  • [latex]0.4x - 1.38 = 0.3x - 1.2[/latex]
  • [latex]1.2 - 0.7x = 2.7 - 0.5x[/latex]
  • [latex]0.43x + 0.25 = 0.29x - 0.03[/latex]
  • [latex]0.6x - 1.2 = 0.9 - 1.5x[/latex]
  • [latex]x - 2 - 4x = -3x - 8 + 5x[/latex]
  • [latex]4(2x - 5) = 32 - 4(x - 2)[/latex]
  • [latex](4 + 6)(2 + 4x) = 45 - 2.5(x + 3)[/latex]
  • [latex](5 + 0.5x)(1 + 3) = -1.2(2x + 4) + 25[/latex]
  • [latex]15 + 5(x - 10) = 3(x - 1)[/latex]
  • [latex]2(x - 3) + 3(x - 5) = 4[/latex]
  • [latex]4(y + 7) - 2(y - 4) = 3(y - 2)[/latex]
  • [latex]8(2y + 4) - 6(3y + 7) = 3y[/latex]
  • [latex]\displaystyle{\frac{x - 7}{2} + \frac{x + 2}{3} = 41}[/latex]
  • [latex]\displaystyle{\frac{7}{12}(2x + 1) + \frac{3}{4}(x + 1) = 3}[/latex]
  • [latex]\displaystyle{\frac{5}{y + 4} = \frac{3}{y - 2}}[/latex]
  • [latex]\displaystyle{\frac{3}{x + 1} = \frac{2}{x - 3}}[/latex]
  • [latex]\displaystyle{\frac{7}{5x - 3} = \frac{5}{4x}}[/latex]
  • [latex]\displaystyle{\frac{5}{y + 2} = \frac{3}{y}}[/latex]

For problems 55 to 76, solve the word problems using algebraic equations.

  • If three times a number plus twenty is seven times that number, what is the number?
  • Fifteen less than three times a number is twice that number. What is the number?
  • A 25-metre-long wire is cut into two pieces. One piece is 7 metres longer than the other. Find the length of each piece.
  • A 9-metre-long pipe is cut into two pieces. One piece is twice the length of the other piece. Find the length of each piece.
  • $500 is shared between Andy and Becky. Andy’s share is $150 less than Becky’s share. Calculate the amount of each of their shares.
  • $200 is shared between Bill and Ann. Ann’s share is $50 more than Bill’s share. Calculate the size of each of their shares.
  • Movie tickets that were sold to each child were $3 cheaper than those sold to each adult. If a family of two adults and two children paid $34 to watch a movie at the cinema, what was the price of each adult ticket and each child ticket?
  • Giri had twice the number of quarters (25 cents) in his bag than dimes (10 cents). If he had a total of 54 coins, how many of them were quarters? What was the total dollar value of these coins?
  • A square garden, with sides of length x metres, is widened by 4 metres and lengthened by 3 metres. Write the equation for the area (A) of the expanded garden. If each side was originally 10 metres in length, find the new area. (Hint: Area of a Rectangle = Length × Width)
  • A square garden, with sides of length x metres, has had its width reduced by 4 metres and its length reduced by 2 metres. Write the equation for the Area (A) of the smaller garden. If each side was originally 20 metres in length, find the new area.
  • Aran bought a shirt and a pair of pants for $34.75. The pair of pants cost $9.75 more than the shirt. Calculate the cost of the shirt.
  • Mythili bought a schoolbag and a toy for $30.45. The school bag cost $5.45 more than the toy. Calculate the cost of the school bag.
  • Sam is paid $720 a week. He worked 9 hours of overtime last week and he received $954. Calculate his overtime rate per hour.
  • Lisa is paid $840 a week. Her overtime rate is $28 per hour. Last week she received $1,036. How many hours of overtime did she work last week?
  • The sum of the three angles of any triangle is 180°. If [latex]3x[/latex], [latex]7x[/latex], and [latex]8x[/latex] are the measures of the three angles of a triangle, calculate the measure of each angle of the triangle.
  • The sum of the three angles of any triangle is 180°. If [latex]3x[/latex], [latex]4x[/latex], and [latex]5x[/latex] are the measures of the three angles of a triangle, calculate the measure of each angle of the triangle.
  • The perimeter of a triangle is the sum of the lengths of the three sides of the triangle. The perimeter of a triangle with sides [latex]x[/latex] cm, [latex](x + 10)[/latex] cm, and [latex]2x[/latex] cm is 70 cm. Calculate the length of each side of the triangle.
  • The perimeter of a triangle is the sum of the lengths of the three sides of the triangle. The perimeter of a triangle with sides [latex]x + 10[/latex], [latex]2x + 10[/latex], and [latex]3x[/latex] is 110 cm. Calculate the length of each side of the triangle.
  • After completing a weight-loss program, a patient weighs 160 lb. His dietician observes that the patient has lost 15% of his original weight. What was the patient’s starting weight?
  • A beaker in a chemistry lab contains 3 litres of water. While conducting an experiment, the chemistry professor removes three-fifths of the water from the beaker. He then adds three-fifths of the remaining volume to the beaker. How much water is left in the beaker at the end of the experiment?
  • A researcher wants to make 4 L of a 7% acid solution. She has a beaker of 15% acid solution in stock. How much of the 15% solution does she need to use and how much water must she add in order to prepare her desired solution?
  • A chemist wants to make a 10% acid solution. She has 5 L of 25% acid solution. How many litres of water should she add to the 25% solution in order to prepare her desired solution?

Unless otherwise indicated, this chapter is an adaptation of the eTextbook  Foundations of Mathe matics  (3 rd  ed.) by Thambyrajah Kugathasan, published by  Vretta-Lyryx Inc ., with permission. Adaptations include supplementing existing material and reordering chapters.

Fundamentals of Business Math Copyright © 2023 by Lisa Koster and Tracey Chase is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License , except where otherwise noted.

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Simplifying Algebraic Expressions - Practice Problems

Now that you've studied the three detailed examples for Simplfying Algebraic Expressions, you are ready to try some on your own! If you haven't studied this lesson yet, click here.

Be very careful as you simplify your terms and make sure that you always take the sign in front of the term as you move things around!

Practice Problems

Simplify each expression to lowest terms.

1. 2a - 4b +3ab -5a +2b

2. 4(2x+1) - 3x

3. 4(p - 5) +3(p +1)

4. 6(p +3q) - (7 +4q)

5. 4rs -2s - 3(rs +1) - 2s

1. -3a - 2b + 3ab

4. 6p + 14q - 7

5. rs - 4s - 3

You're doing a great job! Remember... Algebra skills build on one another, so make sure that you really understand each concept!

problem solving about algebraic expressions

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The algebra section of QuickMath allows you to manipulate mathematical expressions in all sorts of useful ways. At the moment, QuickMath can expand, factor or simplify virtually any expression, cancel common factors within fractions, split fractions up into smaller ('partial') fractions and join two or more fractions together into a single fraction. More specialized commands are on the way.

What is algebra?

Algebra is the branch of elementary mathematics which uses symbols to stand for unknown quantities. In a more basic sense, it consists of solving equations or manipulating expressions which contain symbols (usually letters, like x, y or z) as well as numbers and functions. Although solving equations is really a part of algebra, it is such a big area that it has its own section in QuickMath.

This part of QuickMath deals only with algebraic expressions. These are mathematical statements which contain letters, numbers and functions, but no equals signs. Here are a few examples of simple algebraic expressions :

-1

-2x+1

+3a b-5ab

+1

 + 
-1

The expand command is used mainly to rewrite polynomials with all brackets and whole number powers multiplied out and all like terms collected together. In the advanced section, you also have the option of expanding trigonometric functions, expanding modulo any integer and leaving certain parts of the expression untouched whilst expanding the rest.

Go to the Expand page

The factor command will try to rewrite an expression as a product of smaller expressions. It takes care of such things as taking out common factors, factoring by pairs, quadratic trinomials, differences of two squares, sums and differences of two cubes, and a whole lot more. The advanced section includes options for factoring trigonometric functions, factoring modulo any integer, factoring over the field of Gaussian integers (just the thing for those tricky sums of squares), and even extending the field over which factoring occurs with your own custom extensions.

Go to the Factor page

Simplifying is perhaps the most difficult of all the commands to describe. The way simplification is performed in QuickMath involves looking at many different combinations of transformations of an expression and choosing the one which has the smallest number of parts. Amongst other things, the Simplify command will take care of canceling common factors from the top and bottom of a fraction and collecting like terms. The advanced options allow you to simplify trigonometric functions or to instruct QuickMath to try harder to find a simplified expression.

Go to the Simplify page

The cancel command allows you to cancel out common factors in the denominator and numerator of any fraction appearing in an expression. This command works by canceling the greatest common divisor of the denominator and numerator.

Go to the Cancel page

Partial Fractions

The partial fractions command allows you to split a rational function into a sum or difference of fractions. A rational function is simply a quotient of two polynomials. Any rational function can be written as a sum of fractions, where the denominators of the fractions are powers of the factors of the denominator of the original expression. This command is especially useful if you need to integrate a rational function. By splitting it into partial fractions first, the integration can often be made much simpler.

Go to the Partial Fractions page

Join Fractions

The join fractions command essentially does the reverse of the partial fractions command. It will rewrite a number of fractions which are added or subtracted as a single fraction. The denominator of this single fraction will usually be the lowest common multiple of the denominators of all the fractions being added or subtracted. Any common factors in the numerator and denominator of the answer will automatically be cancelled out.

Go to the Join Fractions page

Introduction to Algebraic Functions

The notion of correspondence is encountered frequently in everyday life. For example, to each book in a library there corresponds the number of pages in the book. As another example, to each human being there corresponds a birth date. To cite a third example, if the temperature of the air is recorded throughout a day, then at each instant of time there is a corresponding temperature.

The examples of correspondences we have given involve two sets X and Y. In our first example, X denotes the set of books in a library and Y the set of positive integers. For each book x in X there corresponds a positive integer y, namely the number of pages in the book. In the second example, if we let X denote the set of all human beings and Y the set of all possible dates, then to each person x in X there corresponds a birth date y.

We sometimes represent correspondences by diagrams of the type shown in Figure 1.17, where the sets X and Y are represented by points within regions in a plane. The curved arrow indicates that the element y of Y corresponds to the element x of X. We have pictured X and Y as different sets. However, X and Y may have elements in common. As a matter of fact, we often have X = Y.

problem solving about algebraic expressions

A function f from a set X to a set Y is a correspondence that assigns to each element x of X a unique element y of Y. The element y is called the image of x under f and is denoted by f(x). The set X is called the domain of the function. The range of the function consists of all images of elements of X.

Earlier, we introduced the notation f(x) for the element of Y which corresponds to x. This is usually read "f of x." We also call f(x) the value of f at x. In terms of the pictorial representation given earlier, we may now sketch a diagram as in Figure 1.18. The curved arrows indicate that the elements f(x), f(w), f(z), and f(a) of Y correspond to the elements x, y, z and a of X. Let us repeat the important fact that to each x in X there is assigned precisely one image f(x) in Y; however, different elements of X such as w and z in Figure 1.18 may have the same image in Y.

problem solving about algebraic expressions

Solution As in Example 1, finding images under f is simply a matter of substituting the appropriate number for x in the expression for f(x). Thus:

problem solving about algebraic expressions

Many formulas which occur in mathematics and the sciences determine functions. As an illustration, the formula A = pi*r 2 for the area A of a circle of radius r assigns to each positive real number r a unique value of A. This determines a function f, where f(r) = pi*r 2 , and we may write A= f(r). The letter r, which represents an arbitrary number from the domain off, is often called an independent variable. The letter A, which represents a number from the range off, is called a dependent variable, since its value depends on the number assigned tor. When two variables r and A are related in this manner, it is customary to use the phrase A is a function of r. To cite another example, if an automobile travels at a uniform rate of 50 miles per hour, then the distance d (miles) traveled in time t (hours) is given by d = 50t and hence the distance d is a function of time t.

We have seen that different elements in the domain of a function may have the same image. If images are always different, then, as in the next definition, the function is called one-to-one.  

Math Topics

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  • Add Fractions
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Algebraic Sentences Problems

Algebraic sentences word problems.

An algebraic sentence when written in equation form involves algebraic expressions (which contain variables such as letters in the alphabet), constants, and an equal symbol. Each algebraic sentence may contain a combination of algebraic expressions and constants, or with just two or more algebraic expressions. Almost always, the word “is” in an algebraic sentence denotes the symbol of equality.

In our example above, the algebraic sentence, “ Five more than twice a number is forty-three “, is translated and written into its equation form: [latex]2x + 5 = 43[/latex].

But before we delve into solving word problems that involve algebraic sentences, it’s crucial that we become familiar with how to translate and write algebraic expressions.

Algebraic Expressions

Learning how to write and translate algebraic expressions is the foundation in writing algebraic sentences. Eventually, we will use this knowledge to write algebraic equations where we solve for the value of the unknown variable.

What is an algebraic expression?

Think of an algebraic expression as the equivalent of a phrase in the English language. It does not convey a complete thought but is an important building block in constructing a sentence. Algebraic expressions consist of numbers, variables, and arithmetic operations.

Let’s take a quick look at some math phrases that were translated and written into algebraic expressions.

  • the sum of a number and [latex]8[/latex] [latex]\large{\,\,\, \to \,\,\,\, {\color{red}{c + 8}}}[/latex]
  • [latex]3[/latex] less than a number [latex]\large{\,\,\, \to \,\,\,\, {\color{red}{y – 3}}}[/latex]
  • the product of [latex]45[/latex] and [latex]m[/latex] [latex]\large{\,\,\, \to \,\,\,\,{\color{red}{45m}}}[/latex]
  • a number divided by [latex]2[/latex] [latex]\large{\,\,\, \to \,\,\,\,\Large {\color{red}{x \over 2}}}[/latex]

Translating and Writing Algebraic Sentences

Once you know how to translate math phrases into algebraic expressions, it’ll be easy for you to translate and write algebraic sentences in an equation form as well.

For instance, how do you write “ the difference of 16 and k is seven ” into an algebraic equation?

Let’s deconstruct this algebraic sentence.

You may notice that we translated “the difference of [latex]16[/latex] and [latex]k[/latex]” into an algebraic expression, [latex]16-k[/latex], then used the equal symbol ([latex]=[/latex]) in place of the word “is”.

As I mentioned at the beginning of this lesson, the word “is” in an algebraic sentence, most of the time, signifies the equality symbol which is the case in this example.

Therefore, we can write this algebraic sentence in equation form as [latex]16 – k = 7[/latex].

Now that we are confident in translating algebraic sentences and writing them in an equation format, it’s time for us to take one step further. We will not only translate and write algebraic sentences into algebraic equations but also proceed to solve them.

Examples of Algebraic Sentences Word Problems

The main key when solving word problems with algebraic sentences is to accurately translate the algebraic expressions then set up and write each algebraic equation correctly. In doing so, we can ensure that we are solving the right equation and as a result, will get the correct answer for each word problem.

Example 1: Six more than seven times a number is thirty-four. Find the number.

First, let’s deconstruct the algebraic sentence. It’s important that we identify and separate the algebraic expressions from the constants as well as determine if the problem suggests equality between the terms.

For the unknown value, we’ll use [latex]\large{x}[/latex] as our variable.

Note: Since addition is commutative, changing the order of the addends on the left side of the equation does not change the sum. Therefore, we may also write the algebraic expression as [latex]7x+6[/latex] or the algebraic equation as [latex]7x + 6 = 34[/latex] instead.

However, for our discussion, we will use [latex]6 + 7x = 34[/latex] as our equation.

The original problem asks us to find the number which in this case is [latex]\large{x}[/latex]. So our next step is to solve for [latex]\large{x}[/latex] in our equation, [latex]6 + 7x = 34[/latex].

Now, we’ll evaluate the value of [latex]\large{x = 4}[/latex] to verify if the number we found satisfies the original algebraic sentence.

Remember that we are asked to find the identity of “the number” in our algebraic sentence and NOT the value of the variable [latex]\large{x}[/latex]. Therefore, it will be incorrect to say that [latex]\large{x=4}[/latex] is the answer. This is a common mistake that we always need to pay attention to.

We’ll replace the variable [latex]\large{x}[/latex] with the number [latex]4[/latex] to see if the algebraic expression on the left side of the equation also results to [latex]34[/latex].

Yes, it does! This means that number 4 is the answer .

Example 2: The difference between three times a number and five is sixteen. Find the number.

Right away, the word “difference” in our algebraic sentence gives us a clue that we will be using the subtraction operation. But, unlike, in addition, the order of the terms within an expression matters in subtraction. So we have to make sure that the terms in our algebraic expression are set up in the correct order.

Another keyword is “times”, which suggests that [latex]3[/latex] is being multiplied to a number whose value is currently unknown.

This time, let’s use [latex]\large{g}[/latex] as our variable. Start by translating the algebraic expression correctly then continue to write the equation.

Now that we have our equation, let’s find out what the unknown value is by solving for the variable, [latex]\large{g}[/latex].

As discussed in our first example, it is important that we verify if the result of our solution makes the algebraic equation true. For this one, I will leave it up to you to evaluate the value of [latex]\large{g = 7}[/latex]. Remember to replace the unknown value of the variable [latex]\large{g}[/latex] with the number [latex]7[/latex] to see if the left side of the equation is also equal to [latex]16[/latex].

Since the original algebraic sentence requires us to find the number, then the answer is number 7 .

Example 3: A number decreased by half of the number is four. Find the number.

This algebraic sentence is quite interesting because we don’t just have one unknown value, but two! First, we have the “number” (the unknown) then the “half of the number”, which means one-half of the unknown.

The keyword “half of” also indicates multiplying something by one-half while the “decreased by” tells us that we will be subtracting one term from the other.

To organize our thoughts, let’s deconstruct this algebraic sentence into its meat and potatoes.

Being able to break apart our algebraic sentence into its basic parts allows us to read the sentence thoroughly and understand the relationship between its quantities.

After setting up our algebraic equation, our next step is to solve it for [latex]\large{m}[/latex].

We need to evaluate the value of [latex]\large{m = 8}[/latex] to check if the number we got makes our algebraic equation true.

Great! The values on both sides of the equation are equal to each other. Therefore, the number 8 is the correct answer to our original algebraic sentence.

Example 4: Four times the sum of twice a number and six is thirty-two. Find the number.

Looking closely, we see a few keywords that would help us in translating this algebraic sentence into an equation.

  • times – means that we’ll be multiplying [latex]4[/latex] by the quantity, “sum of twice a number and six”
  • sum – means that we need to add the terms, “ twice a number ” and six
  • twice – means that a number (the unknown value) is multiplied by [latex]2[/latex]

With these in mind, let’s write our algebraic equation.

Notice that we used the variable [latex]\large{d}[/latex] in our equation to stand for our unknown value. Let’s now proceed and solve for [latex]\large{d}[/latex] and afterward, check if the value we get indeed makes the equation true.

Evaluate the value of [latex]\large{d = 1}[/latex]:

Looks like everything checks out, so the answer to our algebraic sentence is the number 1 .

Example 5: Two-thirds of the sum of three times a number and six is ten. What is the number?

This problem involves a fraction and an algebraic expression as you can tell. The keyword “of” indicates multiplication, so it tells us that we need to multiply the fraction [latex]\large{2 \over 3}[/latex] by the sum of the two given quantities (“three times a number” and six).

Let’s move on and write our algebraic equation. We’ll use the variable [latex]\large{y}[/latex] as the placeholder for our “number” whose value is currently unknown.

Awesome! We are able to translate our algebraic sentence into an equation. It’s time for us to solve for [latex]\large{y}[/latex] then I’ll leave it up to you to do a check if the number we find as the value of [latex]\large{y}[/latex] makes the algebraic equation true.

Once you evaluate [latex]\large{y = 3}[/latex], you’ll see that the answer to our word problem is indeed the number 3 .

Example 6: Twice the difference of a number and three is four more than the number. Find the number.

We have an example here that is a little different from the word problems we’ve covered so far. In this algebraic sentence, both sides of the equation contain an algebraic expression. However, the keywords present will help us translate it correctly into an equation so there’s nothing to worry about.

  • twice – means that we will multiply the quantity (difference of a number and three) by [latex]2[/latex]
  • difference – tells us to use the subtraction operation between our unknown value (“number”) and three
  • more than – means that we need to add four to our unknown value

Let’s solve for our unknown value, [latex]\large{a}[/latex], then verify that our result makes the algebraic equation true.

Evaluate the value of [latex]\large{a = 10}[/latex]:

Perfect! The value we got for [latex]\large{a}[/latex] which is [latex]10[/latex], made our equation equal on both sides. Thus, the answer is the number 10 .

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Algebra Practice Problems – Master Your Skills with Exercises and Solutions!

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Understanding Algebra Fundamentals

Working with equations, practicing algebra with worksheets, mastering fractions and percentages, utilizing algebra in geometry, solving real-world problems.

Algebra Practice Problems Master Your Skills with Exercises and Solutions!

To master algebra , practicing problems and going through their solutions is crucial. It’s a bit like learning to play an instrument – practice is key to improving.

For many students, the leap from arithmetic to algebra can be challenging. It requires a shift from working with concrete numbers to thinking abstractly about numbers and variables. But I’ve found that with a set repertoire of practice problems, from basic equations to more complex ones involving exponents and polynomials, it becomes much clearer.

What’s more, each problem has a set of steps to reach the solution, revealing patterns and strategies that can be applied to future challenges. Having a diverse array of practice problems is beneficial not only for students but also for educators and parents seeking to support their learner’s educational journey.

Hands-on experience with algebraic expressions and equations solidifies understanding and boosts confidence. So let’s get our hands on some algebra problems and start tackling them – who knows what new connections we’ll uncover in the intricacies of algebraic thinking.

Algebra is like a puzzle where I use mathematical symbols and letters (known as variables) to find unknown quantities. Variables represent values that can change; for example, in the equation $x + 2 = 5$, the variable $x$ takes the value $3$.

I need to understand that variables allow me to describe general math truths or perform operations without knowing the exact values.

Here’s what I often start with when exploring fundamental algebraic concepts :

Expressions and Equations : An expression is a combination of numbers and variables, like $3x + 4$. When an expression equals a number, like $3x + 4 = 19$, it becomes an equation. Equations set the stage for finding the value of the variable.

Operations with Variables : I treat variables the same way as numbers in operations. Addition, subtraction, multiplication, and division acts on variables just like on numbers, except that I don’t combine unlike terms (e.g., $x + y$ remains as it is unless I know the relationship between $x$ and $y$).

Below is a simple table detailing how basic arithmetic operations work with variables:

OperationExampleResult
$x + 3$Sum
$x – 2$Difference
$3 \times x$Product
$\frac{x}{4}$Quotient
  • Solving the Equations : To solve an equation, I perform operations that isolate the variable on one side. For example, if $x – 4 = 10$, I add $4$ to both sides to get $x = 14$.

Remembering mathematical order of operations is vital. In algebra, I follow this hierarchy: operations inside parentheses first, exponents second, then multiplication and division, and finally, addition and subtraction. This rule ensures I simplify expressions and solve equations correctly.

When I solve equations, my goal is to isolate the variable I’m interested in. This often involves moving terms from one side of the equation to the other.

For example, in a simple linear equation like ( ax + b = c ), I would solve for ( x ) by subtracting ( b ) from both sides and then dividing by ( a ).

StepEquationExplanation
1( ax + b = c )Original equation
2( ax = c – b )Subtract ( b ) from both sides
3( x = $\frac{c – b}{a}$ )Divide by ( a ) to isolate ( x )

When dealing with absolute values , like ( |x + a| = b ), I remember that the solution considers both the positive and negative counterparts because the absolute value represents the distance from zero without considering direction.

I always check my solutions by substituting them back into the original equation to ensure they satisfy the equation. This verification step is crucial, especially when initial equations involve absolute values or higher degree terms.

For practice problems, Khan Academy and Paul’s Online Math Notes are great resources that offer a variety of algebra problems, including linear equations and absolute value equations. I appreciate how Khan Academy’s platform provides instant feedback.

Working through these problems helps reinforce my understanding. Solving equations can be like a puzzle, and I find it satisfying when I find the correct solution. Each equation brings a new challenge, which keeps my algebra skills sharp and ready.

When I dive into algebra, I find that worksheets are a vital tool for mastering concepts. They offer a structured approach, enabling me to tackle one problem at a time.

While practice problems may vary in complexity, they often share a common focus on fundamental algebraic structures, such as linear equations and variables. 

For linear equations, I often start with simple formats like ( y = mx + b ) and gradually work up to more complex problems. This incremental approach helps me understand the relationship between variables and coefficients.

Sample Linear Equation Worksheet

ProblemSolve for ( y )
( 2x + 3y = 6 )( y = ? )
( 5y – 4x = 10 )( y = ? )
( y + 3 = 3x )( y = ? )

Italicized tip: Always isolate the variable you’re solving for by performing inverse operations.

I make sure worksheets are varied, combining problems that involve solving for one variable with those requiring multiple steps. It’s the repetition and gradual escalation in difficulty that really solidify my understanding.

Variables Practice

  • Identify variables and constants
  • Evaluate expressions like ( 3$x^2$ – 2x + 7 ) for given values of ( x )
  • Translate word problems into algebraic equations

Algebra worksheets offer distinct advantages, as they can be tailored to focus on just the areas I’m looking to improve, providing immediate feedback when answer keys are included. Through disciplined practice , I find myself not just solving problems but also gaining a deeper appreciation of algebra’s expressive power.

I find that a solid grasp of fractions and percentages is crucial in algebra. These concepts are not only foundational in mathematics but also widely applicable in real-world scenarios. Let’s take a closer look at how we can tackle problems involving these topics.

The Fraction Fundamentals For me, working with fractions always starts with understanding the roles of the numerator (top number) and denominator (bottom number). When performing addition or subtraction with fractions, I remember that the denominator must be the same.

For example, to add $$ \frac{3}{4} $$ and $$ \frac{5}{8} $$, I first find a common denominator. Multiplying both the numerator and denominator of $$ \frac{3}{4} $$ by 2 gives me $$ \frac{6}{8} $$. Now, I can easily add the two fractions:

$$ \frac{6}{8} + \frac{5}{8} = \frac{11}{8} $$.

Multiplication and Division Multiplication of fractions is more straightforward. I simply multiply the numerators together and the denominators together. For instance:

$$ \frac{3}{5} \times \frac{2}{3} = \frac{6}{15} $$.

But when it comes to division , I flip the second fraction (find the reciprocal) and then multiply.

$$ \frac{4}{7} \div \frac{2}{5} = \frac{4}{7} \times \frac{5}{2} = \frac{20}{14} $$.

Converting to Percentages When I need to express a fraction as a percent , I multiply the fraction by 100%. For example:

$$ \frac{3}{4} = \frac{3}{4} \times 100% = 75% $$.

To solve for a percentage of a number , I convert the percent to a decimal and then multiply. If I have to find 60% of 50, I do:

$$ 60% = 0.60; \quad 0.60 \times 50 = 30 $$.

By keeping these strategies in mind, I can confidently solve a variety of problems involving fractions and percentages. Experimenting with different problems is an enjoyable way to get better at these concepts!

In exploring the relationship between algebra and geometry, I find it essential to recognize how algebra serves as a robust tool for solving geometric problems. Take the circle, for example; its properties can be unraveled using algebraic methods.

The equation of a circle in a coordinate plane, which is ( $(x – h)^2$ + $(y – k)^2$ = $r^2$ ), allows me to calculate the radius, or find points on its circumference by substituting values for ( x ) and ( y ).

When it comes to finding areas or lengths, algebra is my go-to. For a rectangle or a square, if I know one side and the area, I can easily find the missing side by setting up an algebraic equation. Let’s say the area (( A )) of a rectangle is given and also one side (( l )). The other side (( w )) can be found using ( A = l \times w ).

GivenEquationSolve
( A = 24 )( $w = \frac{A}{l}$ )( $w = \frac{24}{6}$ )
( l = 6 ) ( w = 4 )

In geometry, I also use systems of equations, which is an algebraic approach, to find the intersection between lines, a crucial aspect in defining points in polygons or linear graphs. Here’s a scenario: I have two lines with equations ( y = 2x + 3 ) and ( y = -x + 5 ). Solving this system will give me the exact point where both lines cross.

My journey through geometric challenges often involves these algebraic techniques, showing that algebra isn’t just numbers and letters, it’s a gateway to unlocking the mysteries laid out in shapes and spaces.

When I tackle real-world problems using algebra, I begin by defining the variables that represent the unknowns I’m trying to find. Let’s say I’m trying to figure out how many apples and oranges I can buy with a certain amount of money. I’d let ( x ) represent the number of apples and ( y ) the number of oranges.

I then translate the situation into algebraic equations, usually involving addition, subtraction, multiplication, or division. For instance, if apples cost $2 each and oranges $1.50, and I have $10, the equations would look like this:

[ 2x + 1.5y = 10 ]

Next, I would use function notation to express relationships. If I want to determine the relationship between the cost of fruit and the number I buy, I might write a function:

[ f(x) = 2x ] [ g(y) = 1.5y ]

These equations and functions help me visualize the problem and perform calculations to solve for ( x ) and ( y ).

  • Define variables : Represent unknown quantities with variables.
  • Translate into equations : Use the context to form equations.
  • Function notation : Express relationships with functions.
  • Solve the equations : Find the value of the variables.

Algebra acts as a bridge between basic arithmetic and the more complex real-world scenarios. It allows me to take practical questions and find concrete answers, such as how many items I can purchase or how long a trip might take given a constant speed.

As I practice, I become adept at forming and solving these algebraic equations, making me better equipped to handle similar problems in the future.

In my experience with algebra practice problems and solutions, I’ve observed that consistency is key. Complete a variety of problems from different domains regularly to sharpen skills. It’s essential to tackle problems that challenge various difficulty levels. I’ve appreciated websites like Paul’s Online Math Notes, which provide a range of problems and detailed solutions.

I often use web filters to ensure that my search results come from educational resources, especially those from trusted domains like kastatic.org and kasandbox.org , which are known for their reliable content. Interactive platforms, rather than static worksheets, offer immediate feedback and keep practice engaging.

Khan Academy, for example, offers an interactive approach that I find particularly effective. The immediate feedback helps me adjust my learning path in real-time.

When approaching algebraic word problems , I make sure to define my variables clearly, as this can often simplify complex equations. It’s also crucial to understand concepts like Venn diagrams, which visually represent logical relationships, as they frequently appear in algebra problems.

Consistency, a variety of sources, and clear problem-solving strategies have greatly contributed to my understanding of algebra . Remember, practice doesn’t just make perfect—it makes permanent. So find resources that work for you and stick to them!

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Algebra Problems

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Algebra problems are not only based on algebraic expressions but also on various types of equations in Maths where a quantity or variable is unknown to us. Many of us are familiar with the word problem, but are we aware of the fact and problems related to variables and constants? When we say 5 it means a number but what if we say x=5 or 5y or something like that?

This is where algebra came into existence algebra is that branch of mathematics which not only deals with numbers but also variable and alphabets. The versatility of Algebra is very deep and very conceptual, all the non-numeric character represents variable and numeric as constants. Let us solve some problems based algebra with solutions which will cover the syllabus for class 6, 7, 8. Below are some of the examples of algebraic expressions .

For example.

1. -5y+3=2(4y+12)
2.
3.  x√x=-x
4. |x-a|= a -x
5.
6. log (2 -1)+x=log (144)
7.  

Algebra Word Problems deal with real-time situations and solutions which can be solved using algebra.

Basic Algebra Identities

  • (a + b) 2  = a 2 + b 2 + 2ab
  • (a – b) 2 = a 2  + b 2 – 2ab
  • a 2 – b 2 = (a + b)(a – b)
  • a 2 + b 2 = (a + b) 2 – 2ab = (a – b) 2 + 2ab
  • a 3 + b 3 = (a + b)(a 2 – ab + b 2 )
  • a 3 – b 3 = (a – b)(a 2 + ab + b 2 )
  • (a + b) 3 = a 3 + 3ab(a + b) + b 3
  • (a – b) 3 = a 3 – 3ab(a – b) – b 3

Algebra problems With Solutions

Example 1: Solve, (x-1) 2 = [4√(x-4)] 2 Solution: x 2 -2x+1 = 16(x-4)

x 2 -2x+1 = 16x-64

x 2 -18x+65 = 0

(x-13) (x-5) = 0

Hence, x = 13 and x = 5.

Algebra Problems for Class 6

In class 6, students will be introduced with an algebra concept. Here, you will learn how the unknown values are represented in terms of variables.  The given expression can be solved only if we know the value of unknown variable. Let us see some examples.

Example: Solve, 4x + 5 when, x = 3.

Solution: Given, 4x + 5

Now putting the value of x=3, we get;

4 (3) + 5 = 12 + 5 = 17.

Example: Give expressions for the following cases:

(i) 12 added to 2x

(ii) 6 multiplied by y

(iii) 25 subtracted from z

(iv) 17 times of m 

(i) 12 + 2x

Algebra Problems for Class 7

In class 7, students will deal with algebraic expressions like x+y, xy, 32x 2 -12y 2 , etc. There are different kinds of the terminology used in case algebraic equations such as;

  • Coefficient

Let us understand these terms with an example. Suppose 4x + 5y is an algebraic expression, then 4x and 5y are the terms. Since here the variables used are x and y, therefore, x and y are the factors of 4x + 5y. And the numerical factor attached to the variables are the coefficient such as 4 and 5 are the coefficient of x and y in the given expression.

Any expression with one or more terms is called a polynomial. Specifically, a one-term expression is called a monomial; a two-term expression is called a binomial, and a three-term expression is called a trinomial.

Terms which have the same algebraic factors are like terms . Terms which have different algebraic factors are unlike terms . Thus, terms 4xy and – 3xy are like terms; but terms 4xy and – 3x are not like terms.

Example: Add 3x + 5x

Solution: Since 3x and 5x have the same algebraic factors, hence, they are like terms and can be added by their coefficient.

3x + 5x = 8x

Example: Collect like terms and simplify the expression: 12x 2 – 9x + 5x – 4x 2 – 7x + 10.

Solution: 12x 2 – 9x + 5x – 4x 2 – 7x + 10

= (12 – 4)x 2 – 9x + 5x – 7x + 10

=  8x 2 – 11x + 10

Algebra Problems for Class 8

Here, students will deal with algebraic identities. See the examples.

Example: Solve (2x+y) 2

Solution: Using the identity: (a+b) 2  = a 2 + b 2 + 2 ab, we get;

(2x+y) = (2x) 2 + y 2 + 2.2x.y = 4x 2 + y 2 + 4xy

Example: Solve (99) 2 using algebraic identity.

Solution: We can write, 99 = 100 -1

Therefore, (100 – 1 ) 2

= 100 2 + 1 2 – 2 x 100 x 1  [By identity: (a -b) 2 = a 2 + b 2 – 2ab

= 10000 + 1 – 200

Algebra Word Problems

Question 1: There are 47 boys in the class. This is three more than four times the number of girls. How many girls are there in the class?

Solution: Let the number of girls be x

As per the given statement,

4 x + 3 = 47

4x = 47 – 3

Question 2: The sum of two consecutive numbers is 41. What are the numbers?

Solution: Let one of the numbers be x.

Then the other number will x+1

Now, as per the given questions,

x + x + 1 = 41

2x + 1 = 41

So, the first number is 20 and second number is 20+1 = 21

Linear Algebra Problems

There are various methods For Solving the Linear Equations

  • Cross multiplication method
  • Replacement method or Substitution method
  • Hit and trial method

There are Variety of different Algebra problem present and are solved depending upon their functionality and state. For example, a linear equation problem can’t be solved using a quadratic equation formula and vice verse for, e.g., x+x/2=7 then solve for x is an equation in one variable for x which can be satisfied by only one value of x. Whereas x 2 +5x+6 is a quadratic equation which is satisfied for two values of x the domain of algebra is huge and vast so for more information. Visit BYJU’S. where different techniques are explained different algebra problem.

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Simplifying Algebraic Expressions

Simplifying algebraic expressions is a fundamental skill in algebra that helps in solving equations, graphing functions and understanding mathematical relationships. This process involves reducing the expressions to their simplest form by combining like terms, applying mathematical operations and following the algebraic rules. This article will guide us through the essential steps, rules and techniques for simplifying algebraic expressions, along with examples and practice problems to enhance our understanding.

Table of Content

  • Understanding Algebraic Expressions

Combining Like Terms

Applying the distributive property, combining distributive property and like terms, using the foil method.

  • Examples with Solutions
  • Practical Questions

What are Algebraic Expressions?

An algebraic expression is a combination of numbers, variables and mathematical operators (such as +, -, × and /). For example:

3x + 5 − 2x

In this expression, 3x and −2x are like terms, while 5 is a constant term.

Terms are terms that have the same variable raised to the same power. To simplify an expression combine these terms by performing the arithmetic operations.

Example: Simplify the expression 4x + 7 − 3x + 2.

  • Combine 4x and −3x: 4x − 3x = x
  • Combine 7 and 2: 7 + 2 = 9
  • The simplified expression is x + 9.

The distributive property states that a(b + c) = ab + ac. Use this property to the eliminate parentheses in an expression.

Example: Simplify the expression 3(x + 4).

Apply the distributive property: 3(x + 4) = 3⋅x + 3⋅4 Perform the multiplication: 3x + 12 The simplified expression is 3x+12.

In more complex expressions, use both the distributive property and combining like terms to the simplify.

Example: Simplify the expression 2(x − 3) + 4x.

Apply the distributive property: 2(x − 3) = 2x − 6 Combine with 4x: 2x − 6 + 4x Combine like terms: 2x + 4x = 6x Simplified expression: 6x − 6

The FOIL method is used to the simplify the product of the two binomials. The FOIL stands for First, Outer, Inner, Last referring to the terms to be multiplied.

Example: Simplify (x + 2)(x + 3) using the FOIL method.

First: x ⋅ x = x 2 Outer: x⋅3 = 3x Inner: 2⋅x = 2x Last: 2⋅3 = 6 Combine the results: x 2 + 3x + 2x + 6 Combine like terms: x 2 + 5x + 6 The simplified expression is x 2 + 5x + 6.

Solved Examples on Simplifying Algebraic Expressions

Example 1: Simplify 4x + 3 − 2x + 5.

Combine like terms: 4x − 2x + 3 + 5. Perform the addition/subtraction: 2x + 8. The simplified expression is 2x + 8.

Example 2: Simplify 3(a+4)−2(a−1).

Apply the distributive property: 3(a + 4) = 3a + 12 −2(a − 1) = −2a + 2 Combine the results: 3a + 12 − 2a + 2 Combine like terms: 3a − 2a + 12 + 2. Perform the addition/subtraction: a + 14. The simplified expression is a + 14.

Example 3: Simplify [Tex]\frac{6x^2 – 3x + 2x^2 + 5}{2}[/Tex] .

Combine like terms in the numerator: [Tex]6x^2 + 2x^2 – 3x + 5 = 8x^2 – 3x + 5 [/Tex] Divide each term by 2: [Tex]\frac{8x^2}{2} – \frac{3x}{2} + \frac{5}{2} = 4x^2 – \frac{3x}{2} + \frac{5}{2} [/Tex] The simplified expression is [Tex]4x^2 – \frac{3x}{2} + \frac{5}{2}[/Tex] .

Example 4: Simplify (x + 2)(x – 3).

Use the FOIL method: First: [Tex]x \cdot x = x^2[/Tex] Outer: [Tex]x \cdot (-3) = -3x[/Tex] Inner: [Tex]2 \cdot x = 2x[/Tex] Last: [Tex]2 \cdot (-3) = -6[/Tex] Combine the results: [Tex]x^2 – 3x + 2x – 6 = x^2 – x – 6 [/Tex] The simplified expression is [Tex]x^2 – x – 6[/Tex] .

Example 5: Simplify [Tex]\frac{2(x + 4) – 3(x – 2)}{x}[/Tex] .

Apply the distributive property in the numerator: [Tex]2(x + 4) = 2x + 8 [/Tex] [Tex]-3(x – 2) = -3x + 6 [/Tex] Combine the results: [Tex]2x + 8 – 3x + 6 = -x + 14[/Tex] Divide by x: [Tex]\frac{-x + 14}{x} = -1 + \frac{14}{x}[/Tex] The simplified expression is [Tex]-1 + \frac{14}{x}[/Tex] .

Practice Questions

Q1: Simplify: [Tex]7m – 4n + 2m – 3n[/Tex] .

Q2: Simplify: [Tex]\frac{5x^2 – 2x + 3x^2 – 4}{3}[/Tex] .

Q3: Simplify: (2x + 1)(x – 2) + 3(x + 1).

Q4: Simplify: [Tex]\frac{4y – 3(2y – 1)}{y}[/Tex] .

Q5: Simplify: 5(a + 3b) – 2(a – b).

Q6: Simplify: [Tex](3x – 4)^2 – (x – 2)^2[/Tex] .

Q7: Simplify: 6 – 2(3 – x) + 4x.

Q8: Simplify: [Tex]\frac{3(x^2 – 4) + 2(x^2 + 1)}{x}[/Tex] .

Q9: Simplify: (x + 2)(x + 3) – (x – 1)(x – 2).

Q10: Simplify: 2(3x – 5) + 4x – 7x.

What is the difference between combining like terms and applying the distributive property?

The Combining like terms involves adding or subtracting terms with the same variables. The distributive property involves the multiplying a term by the sum or difference inside parentheses.

How do you handle negative signs when simplifying expressions?

Be careful with the negative signs by the distributing them correctly across the terms in the parentheses and combining them properly with the other terms.

Can algebraic expressions have more than one variable?

Yes, expressions can have multiple variables. Simplify them by the combining like terms that share the same variables and powers.

What is a binomial?

A binomial is a polynomial with the exactly two terms such as the x+3 or 2x 2 -y.

Why is it important to simplify algebraic expressions?

The Simplifying expressions helps in the solving the equations making calculations easier and understanding the mathematical relationships more clearly.

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COMMENTS

  1. How to Solve an Algebraic Expression: 10 Steps (with Pictures)

    First, move everything that isn't under the radical sign to the other side of the equation: √ (2x+9) = 5. Then, square both sides to remove the radical: (√ (2x+9)) 2 = 5 2 =. 2x + 9 = 25. Now, solve the equation as you normally would by combining the constants and isolating the variable: 2x = 25 - 9 =. 2x = 16.

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    About this unit. The core idea in algebra is using letters to represent relationships between numbers without specifying what those numbers are! Let's explore the basics of communicating in algebraic expressions.

  3. Algebraic Expressions Questions

    Practice Questions on Algebraic Expressions. Find the value of the expression a 2 + 3b 2 + 6ab for a = 1 and b = - 2. Find the number of terms of the expression 3x 2 y - 2y 2 z - z 2 x + + 4xy - 5. Simplify the expression 50x 3 - 21x + 107 + 41x 3 - x + 1 - 93 + 71x - 31x 3. Add the following expressions:

  4. 1.4: Algebraic Expressions and Formulas

    Terms 88 in an algebraic expression are separated by addition operators and factors 89 are separated by multiplication operators. The numerical factor of a term is called the coefficient 90.For example, the algebraic expression \(x^{2} y^{2} + 6xy − 3\) can be thought of as \(x^{2} y^{2} + 6xy + (−3)\) and has three terms.

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    Examples, solutions, videos, worksheets, games and activities to help Algebra 1 or grade 7 students learn how to write algebraic expressions from word problems. Beginning Algebra & Word Problem Steps. Name what x is. Define everything in the problem in terms of x. Write the equation.

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    7.3 Simple Algebraic Equations and Word Problems. An algebraic equation is a mathematical sentence expressing equality between two algebraic expressions (or an algebraic expression and a number). When two expressions are joined by an equal (=) sign, it indicates that the expression to the left of the equal sign is identical in value to the ...

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    Simplifying Algebraic Expressions - Practice Problems. Now that you've studied the three detailed examples for Simplfying Algebraic Expressions, you are ready to try some on your own! If you haven't studied this lesson yet, click here. Be very careful as you simplify your terms and make sure that you always take the sign in front of the term as you move things around!

  12. Solve equations, simplify expressions with Step-by-Step Math Problem Solver

    This part of QuickMath deals only with algebraic expressions. These are mathematical statements which contain letters, numbers and functions, but no equals signs. Here are a few examples of simple algebraic expressions : x 2 -1. x 2 -2x+1. ab 2 +3a 3 b-5ab. x 3 +1. 1. a + b.

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    Solution. Following "Tips for Evaluating Algebraic Expressions," first replace all occurrences of variables in the expression (a − b) 2 with open parentheses. (a − b)2 = (() − ())2 (a − b) 2 = (() − ()) 2. Secondly, replace each variable with its given value, and thirdly, follow the "Rules Guiding Order of Operations" to ...

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    Algebra Calculator is a calculator that gives step-by-step help on algebra problems. See More Examples » x+3=5. 1/3 + 1/4. y=x^2+1. Disclaimer: This calculator is not perfect. Please use at your own risk, and please alert us if something isn't working. ... If you would like to create your own math expressions, here are some symbols that the ...

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    Let us solve some problems based algebra with solutions which will cover the syllabus for class 6, 7, 8. Below are some of the examples of algebraic expressions. For example. 1.-5y+3=2(4y+12) 2. ... Suppose 4x + 5y is an algebraic expression, then 4x and 5y are the terms. Since here the variables used are x and y, therefore, x and y are the ...

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    Subtraction of Algebraic Expressions refers to combining like terms together and then subtracting their numeral coefficients. Subtracting algebraic expressions involves combining like terms with attention to the signs. Subtraction of algebraic expression is a widely used concept used for problem-solving. In this article, we will learn the concept o

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