Practice Isolating Variable in Math

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

Quick Recap

Rearranging an equation by applying inverse operations until the variable stands alone on one side.

Peel away everything around x until only x remains: x= answer.

Showing a random 20 of 59 problems.

Example 1

challenge
Solve for x: ax+b=c (with a≠0), in terms of a,b,c.

Example 2

medium
Isolate x: 2(x+3)=14.

Example 3

medium
Solve for h: V=πr2h.

Example 4

easy
Isolate x: x+8=15.

Example 5

hard
Solve for r: A=P(1+rt) (simple interest).

Example 6

challenge
Solve for x: log⁡2(x−1)+log⁡2(x+1)=3.

Example 7

easy
Solve for x: 2x3=8.

Example 8

hard
Solve for x: 2(3x−1)−4(x+5)=6.

Example 9

medium
Solve for b: A=a+b2.

Example 10

medium
Solve for r: C=2πr.

Example 11

easy
Isolate x: 2x=7.

Example 12

easy
Solve for x: −3x=21.

Example 13

easy
Isolate x: x+12=2.

Example 14

medium
Isolate x: 5x−3=2x+9.

Example 15

hard
Solve for x in terms of a,b: x−ab=x+ba (a,b≠0, a≠b).

Example 16

easy
Fill in the blank so that the solution is x=6: x2+__=10.

Example 17

medium
Solve for x: x−34=x+16.

Example 18

medium
Solve for x: 3(x−4)=18.

Example 19

hard
Solve for x: 2x+5=7.

Example 20

easy
Solve for x: x+12=5.