Réponses

2013-10-09T18:35:46+02:00
Bonsoir
a)  -3a +2 = 3a +14
     -3a -3a = 14 -2
     - 6a = 12
a = -12/6 = -2

b) 2a +7 = -2a -3
2a +2a = -3 -7
4a = -10
a = -10/4 = - 5/2

c) 3a -11 = -5a +4
3a +5a = 4 +11
8a = 15
a = 15/8

d) -a -5 = 3a +1
- a-3a = 1+5
-4a = 6
a = -6/4 = -3/2