Question

УПРОСТИТЕ ПЖЖЖ!!!!!!!!15 БАЛЛОВ!!!!!!!!ЛЕГКО!!!!!!!!!
x^2-9x/x^2-81
при x=-12

Answer 1

x^2-9x = x(x-9)
x^2-81 = (x-9)(x+9)

(x(x-9))  /  (x-9)(x+9) = x/(x+9) = -12/(-12+9) =4