Réponse :
Bonjour
Explications étape par étape
A = (-9x-1)(6x+8)-(4x-10)(6x+8)
A = (6x+8)[(-9x-1)-(4x-10)]
A = (6x+8)(-9x-1-4x+10)
A = (6x+8)(-13x+9)
A = 2(3x+4)(-13x+9)
B = (7x+7)(8x-7)-(5-10x)(7x+7)
B = (7x+7)[(8x-7)-(5-10x)]
B = (7x+7)(8x-7-5+10x)
B = (7x+7)(18x-12)
B = 7(x+1) * 6(3x-2)
B = 42(x+1)(3x-2)