Find the difference

Question

(-x^2+8x-7)-(9x^2-5x-7)

Answer 1

1. Remove the 1st parenthesis.

2. Remove the 2nd parenthesis by multiplying each term by (-1):

-X^2+8X-7 - 9X^2+5X+7.
3. Combine like-terms and get:
-10X^2 + 13X.