Answer:
5b - 5a
Step-by-step explanation:
b(5 - a) = 5b - ab
- a(b - 5) = - ab + 5a
Subtracting gives
5b - ab - (- ab + 5a) ← distribute parenthesis by - 1
= 5b - ab + ab - 5a ← collect like terms
= 5b - 5a