Answer:
0
Step-by-step explanation:
Given
a + 7(a + b) - 8(a + b) + b ← distribute both parenthesis
= a + 7a + 7b - 8a - 8b + b ← collect like terms
= a + 7a - 8a + 7b - 8b + b
= 0
a+7a+7b-8a-8b+b
combining like terms
a+7a-8a+b+7b-8b
8a-8a+8b-8b
