show that x-a is a factor of x^2(a-b) + a^2(b-x)-b^2(x-a)

Question

i dont understand how to even start this problem im really confused

Answer 1

x^2(a-b) + a^2(b-x)-b^2(x-a) =

ax^2 - bx^2 + ba^2 - xa^2 - b^2(x - a) =

ax(x -a) - b(x^2 -a^2) - b^2(x - a) =

ax(x - a) - b(x - a)(x+a) - b^2(x - a) =

(x - a){ax - b(x+a) - b^2)}