Question

1. What mistake did he make in the process?

Answer 1

1. Mich forgot to subtract the 3x to the x in the numerator, and he forgot to simply 4 to 2

2. His numerator should be - 2

3. His denominator should be 2x

His final answer should be

-2/2x = -x

Answer 2

His mistake was in the last step. You can only cancel like terms when the terms are multiplied , here they are added or subtracted.