Réponses

2014-02-25T17:55:31+01:00
A) 2x+7+3x=6x-13
5x+7=6x-13
5x-5x+7+13=6x-5x-13+13
20=x

B)
-2x+2<x+12
-2x+2x+2-12<x+2x+12-12
-10<3x
x>-10/3