Solving Equations · One-step equations · 2.4

Multiply to solve.

When x is divided by a number, multiply both sides by it. x/3 = 4 → multiply by 3 → x = 12.

01 / THE IDEA

See it work.

Watch the method

Multiply to solve

x/3 = 4 → multiply both sides by 3 → x = 12.

1 / 2
x/3=4x/3 = 4
1

The equation

Solve for x — find the value that makes both sides equal.

13x=4\frac{1}{3}x = 4
2

Multiply both sides by 3

x is divided by 3, so multiply both sides by 3 to undo it.

x=12x = 12
02 / YOUR TURN

Practice until it feels automatic.

Your turn

Solve for x.

Type the value of x — a number or a fraction like 3/2.

streak 0
best 0
…x =
— / WHY IT WORKS

The idea underneath.

Multiply to undo a divide

If x/a = b, then x = b × a (multiply both sides by a).

Why it works

x/3 = 4 means a third of x is 4.

03 / WORKED EXAMPLES

From easy to tricky.

EX 1easy

Solve x/3 = 6

1

The equation

Solve for x — find the value that makes both sides equal. 1/3x = 6

2

Multiply both sides by 3

x is divided by 3, so multiply both sides by 3 to undo it. x = 18

EX 2medium

Solve x/6 = 7

1

The equation

Solve for x — find the value that makes both sides equal. 1/6x = 7

2

Multiply both sides by 6

x is divided by 6, so multiply both sides by 6 to undo it. x = 42

EX 3hard

Solve x/3 = 4

1

The equation

Solve for x — find the value that makes both sides equal. 1/3x = 4

2

Multiply both sides by 3

x is divided by 3, so multiply both sides by 3 to undo it. x = 12

04 / COMMON TRAPS

Where students slip.

Trap

Dividing instead of multiplying.

Fix

To undo ÷3, multiply by 3.

Trap

Multiplying one side only.

Fix

Multiply both sides by the divisor.

05 / QUIZ

Test yourself.

The Test

12 problems across three tiers. Auto-graded on submit. Hints and a full walkthrough on every question. Your work is saved on this device — sign in to keep it across devices.

0/12Answered
How to answerType just the value. Formatting won't trip you up — we ignore spaces, capital letters, commas, and subscript style, so t₁ = 5, d = 3 and t1=5,d=3 both count. For a list of numbers, separate them with commas (e.g. 3, 10, 17).
Core

Core (4)

C1

Solve x/2 = 2

Need a hint?
  • Multiply by the number under x.
  • Do it to both sides.
C2

Solve x/2 = 8

Need a hint?
  • Multiply by the number under x.
  • Do it to both sides.
C3

Solve x/2 = 8

Need a hint?
  • Multiply by the number under x.
  • Do it to both sides.
C4

Solve x/2 = 4

Need a hint?
  • Multiply by the number under x.
  • Do it to both sides.
Apply

Apply (4)

A1

Solve x/4 = 7

Need a hint?
  • Multiply by the number under x.
  • Do it to both sides.
A2

Solve x/4 = 5

Need a hint?
  • Multiply by the number under x.
  • Do it to both sides.
A3

Solve x/6 = 9

Need a hint?
  • Multiply by the number under x.
  • Do it to both sides.
A4

Solve x/4 = 5

Need a hint?
  • Multiply by the number under x.
  • Do it to both sides.
Extension

Extension (4)

E1

Solve x/4 = 8

Need a hint?
  • Multiply by the number under x.
  • Do it to both sides.
E2

Solve x/2 = 9

Need a hint?
  • Multiply by the number under x.
  • Do it to both sides.
E3

Solve x/6 = 2

Need a hint?
  • Multiply by the number under x.
  • Do it to both sides.
E4

Solve x/2 = 2

Need a hint?
  • Multiply by the number under x.
  • Do it to both sides.