7. 36c^2 - 20c^2 - 32c
8. 5y^2 + 17y - 12
9. 5s^3 + 32s^2 - 13s - 10
10. 16p^2 - 1
11. w^2 - 10w + 25
12. 4b^2 + 12b + 9
have a wonderful day! if you need me to explain the steps for all of them in the comments! :)
(p^2 - 5p + 4) - (4p^2 - 9p + 11)
= p^2 - 5p + 4 - 4p^2 + 9p - 11
= p^2 - 4p^2 -5p + 9p + 4 - 11
= -3p^2 + 4p - 7
Answer:

Step-by-step explanation:

The radical symbol when used for a square root means the non-negative square root. You cannot state that sqrt(x^2) = x because x may be negative. That is why you need use the absolute value symbol.