Réponses

2014-05-03T13:45:02+02:00
Bonjour

(7 -3x)(x+3) = (x-3)(x+3)
(7-3x)(x+3)- (x-3)(x+3) = 0
(x+3)(7-3x - x -3) = 0
(x+3)(-4x +4) = 0
soit x+3 = 0
x = -3

soit -4x +4 = 0
-4x = -4
x = 1