(x^2-x)^2-18(x^2-x)+72
=(x^2-x-6)(x^2-x-12)
=(x-3)(x+2)(x-4)(x+3)
(x+1)(x+2)-x-10
=x^2+3x+2-x-10
=x^2+2x-8
=(x+4)(x-2)