Question

Select the step in the solution that shows the first error.

Step 1: 20x - 10 = 80 + 10x
Step 2: 20x = 80 + 10x
Step 3: 10x = 80
Step 4: x= 8

Answer 1

Step 2: 20x = 80 + 10x

Explanation:

Step 1: 20x - 10 = 80 + 10x

Add 10 to each side

20x - 10+10 = 80+10 + 10x

20x = 90 + 10x

Step 2: 20x = 80 + 10x This has the first error

Step 3: 10x = 80

Step 4: x= 8