Réponses

2014-09-22T22:57:05+02:00
5 - 3 (2x + 5) = 4x - 7
5 - 6x - 15 = 4x - 7
- 6x - 4x = - 7 - 5 + 15
- 10x = 3
x = - 3/10
x = - 0,3

8 - 5 (2x - 2) = 8x + 4
8 - 10x + 10 = 8x + 4
- 10x - 8x = 4 - 8 - 10
- 18x = - 14
x = 14/18
x = 7/9

-4x + 7 = 5 - 5 (x + 6)

- 4x + 7 = 5 - 5x - 30
- 4x + 5x = 5 - 30 - 7
x = - 32