Question

Describe and correct the error in finding the difference.

Answer 1

final answer should be - 2m + 24

(4m + 9) - 3(2m - 5 ) → (distributing gives)

4m + 9 - 6m + 15 → ( error in original has - 15 )

collect like terms

(4m - 6m ) + (9 + 15) = - 2m + 24

Answer 2

1. in the distributive -3(2m - 5), one forget to use the positive sign instead of the negative sign.

2. the answer should be -2m + 24