(a-8)(a+7)-(a+10)(a-11)

Question

(a-8)(a+7)-(a+10)(a-11)

Answer 1

(a-8)(a+7) - (a+10)(a-11) = a^2-a-56 - (a^2-a-110) = a^2-a-56-a^2+ a+110 = 54