Réponses

2014-05-12T21:22:15+02:00
6a +7= 3a -3
6a +7 -7 -3a= 3a -3 -7 -3a
3a= -10
3a/3= -10/3
a= -10/3
2014-05-12T21:36:21+02:00
6a + 7 = 3a - 3
6a - 3a = - 3 - 7
3a = - 10
a = -10/3