Réponses

2014-09-11T17:49:20+02:00
 - 3x - 8 = - 7x - 4 
- 3x - 8 + 7x + 4 = 0
4x - 4 = 0

4x=4
x=1

7x - 6 = 6x + 3
7x - 6 - 6x - 3 = 0
x- 9=0

x=9

Meilleure réponse !
2014-09-11T18:02:17+02:00
A) -3x - 8 = -7x - 4
-3x + 7x = 8 - 4
4x = 4
x = 1

b) 7x - 6 = 6x + 3
7x - 6x = 6 + 3
x = 9