Respuesta :

(7a-b+3)-(-2a-8b+8)
Apply plus/minus rule.
-(-a)= a and -(a)=-a
we get
(7a-b+3)-(-2a-8b+8)= 7a-b+3+2a+8b-8
Add like terms
=9a+7b-5

Answer: 9a + 7b - 5