Answer :
5a + 2a(5 + (-b)) = 5a + 2a(5 - b)
Use the distributive property which states a(b+c) = ab + ac
5a + 10a - 2ab
Simplify like terms
15a - 2ab
Use the distributive property which states a(b+c) = ab + ac
5a + 10a - 2ab
Simplify like terms
15a - 2ab