Verified answer

EX11 : Factorise les expressions suivantes :

A = (x + 3)(x + 5) - 3(x + 5) = (x + 5)(x + 3 - 3) = x(x + 5)

B = (2 x + 3)(x - 4) + (3 x - 5)(x - 4) = (x - 4)(2 x + 3 + 3 x - 5) = (x - 4)(5 x - 2)

C = x(2 x + 3) - 7(2 x + 3) = (2 x + 3)(x - 7)

D = (3 x - 1)(x - 2) - (2 x - 5)(3 x - 1) = (3 x - 1)(x - 2 - 2 x + 5) = (3 x - 1)(3 - x)