Réponses

2014-05-01T14:21:24+02:00
7x + 8 = 29 
7x + 8 - 8 = 29-8
7x = 21
7x/7 = 21/7
x = 3

-6d-8 = 34 
-6d-8+8 = 34+8
-6d = 42
-6d/-6 = 42/-6
d=-7


exo 4 : 
9y-12=5y-4 
9y-12-5y=5y-4-5y
4y-12=-4
4y-12+12=-4+12
4y=8
4y/4=8/4
y=2

-8s+76 =7s+16
-8s+76-7s=7s-7s+16
-15s+76=16
-15s+76-76=16-76
-15s=-60 
-15s/-15=-60/-15
s=4
7x+8=29
7*3+8=29
29=29
Ta compris ?
Oui c bon excuse je beug