Solve Simple Linear Equations with Unknowns on Each Side

Follow this example and the steps used to solve this simple equation with unknowns on both sides.

Example

3x - 4 = 5x - 20

Method

Reverse so that the bigger x term is on the left (this move is optional but makes it easier)

5x - 20 = 3x - 4

Subtract 3x from both sides:

2x - 20 = -4

Add 20 to both sides:

2x = 16

Divide both sides by 2:

x = 8

Check answer

Substitute x = 8 into the original equation 3x - 4 = 5x - 20

Left-hand side = 3 x 8 - 4 = 24 - 4 = 20

Right-hand side = 5 x 8 - 20 = 40 - 20 = 20

Let's have a go at some questions now.