Practice Equivalence Transformation in Math

Use these practice problems to test your method after reviewing the concept explanation and worked examples.

Quick Recap

Operations applied to both sides of an equation that transform its form while leaving its solution set completely unchanged.

Whatever you do to one side, do to the other โ€” the balance stays true.

Showing a random 20 of 59 problems.

Example 1

easy
Solve x+4=9x+4=9 using an equivalence transformation.

Example 2

easy
Solve xโˆ’3=7x-3=7.

Example 3

hard
Solve the system {2x+y=7xโˆ’y=โˆ’1\begin{cases}2x + y = 7 \\ x - y = -1\end{cases} using equivalence transformations.

Example 4

easy
True or false: subtracting the same expression from both sides of an equation always yields an equivalent equation.

Example 5

medium
Priya and Sam have exactly the same amount of money. Each of them spends 44 dollars on lunch. Priya now has 1313 dollars. How many dollars does Sam have now?

Example 6

medium
Why is squaring both sides of an equation NOT always an equivalence transformation?

Example 7

challenge
Find all xx satisfying x2โˆ’4xโˆ’2=5\frac{x^2 - 4}{x - 2} = 5 and state any restrictions.

Example 8

medium
Solve 3x+5=203x+5=20.

Example 9

medium
Fill the blank so the solution is x=5x = 5: 3xโˆ’__=113x - \_\_ = 11

Example 10

medium
Solve 2x+35=3\frac{2x+3}{5} = 3.

Example 11

medium
Ben solves 3x=243x = 24 like this: he divides the left side by 33 but subtracts 33 on the right, writing x=24โˆ’3=21x = 24 - 3 = 21. Find his mistake and enter the correct value of xx.

Example 12

medium
Why is multiplying both sides of 1x=2\frac{1}{x} = 2 by xx usually safe here?

Example 13

medium
Solve 6xโˆ’4=2x+126x - 4 = 2x + 12.

Example 14

hard
Solve 2x+1=xโˆ’1\sqrt{2x+1} = x - 1 and identify any extraneous solutions.

Example 15

medium
True or false: multiplying both sides of x=3x = 3 by (xโˆ’3)(x-3) yields an equivalent equation.

Example 16

medium
Fill in: To remove the fraction in x3โˆ’1=4\frac{x}{3} - 1 = 4, you can ___ both sides by 3 first or after adding 1.

Example 17

medium
Show that 3(xโˆ’2)=93(x-2) = 9 and xโˆ’2=3x - 2 = 3 are equivalent equations.

Example 18

easy
Solve x+10=4x+10=4.

Example 19

hard
Solve the inequality โˆ’2x+5โ‰ฅ11-2x + 5 \geq 11.

Example 20

medium
Solve โˆ’3x+7=1-3x + 7 = 1.