Réponse:
a) (2 x + 4)(3 x - 6) + (2 x + 4) (4 x - 3)=0
(2x+4)(3x-6 + 4x-3) = 0
(2x+4)(7x -9) = 0
2x +4 = 0
2x = -4
2x/2 = -4/2
x = -2
7x -9 = 0
7x = 9
7x/7 = 9/7
x = 9/7
L'équation a deux solutions : -2 et 9/7
c) (x+2)2 -9 =0
2x +4 -9 = 0
2x = 9-4
2x = 5
2x/2 = 5/2
x = 5/2
b) (x+3)2 - (x+3)(5x -8) = 0
(x+3)(2 - 5x +8) =0
(x+3)(10 -5x) = 0
x+3 = 0
x = -3
10 -5x =0
-5x = -10
-5x/-5 = -10/-5
x = 2
L'équation a deux solutions : -3 et 2
d) (3x +4)2 -(2x-7)2 = 0
2(3x +4 -2x+7) =0
2(x +11) = 0
2x +22 = 0
2x = -22
2x/2 = -22/2
x =-11
