Réponse:
Bonsoir
Explications étape par étape:
a. 5x - 7 = 2x + 8
5x - 2x = 8 + 7
3x = 15
x = 15/3
a. x = 5
b. 2(3x - 4) = -7x + 9
6x - 8 = -7x + 9
6x + 7x = 9 + 8
13x = 17
b. x = 17/13
c. (4x - 3) - 8 = 5x - (2x - 3)
4x - 3 - 8 = 5x - 2x + 3
4x - 11 = 3x + 3
4x - 3x = 3 + 11
c. x = 14