Réponse :
Explications étape par étape
Bonjour,
A)
-8-2 = 11x -5x
-10 = 6x
x= -10/6 = -5/3
B)
4a -28 = 5-a+7
4a+a = 28 +5 +7
5a = 40
a= 40/5 = 8
C)
5m+10 -2m = 9 +3m
5m-2m-3m = 9-10
0 = -1
faux!
D)
3x+15 +5X = 2x -16 +13
3x+15x -2x= -16+13 -15
16x = -18
x= -18/16 = -9/8
E)
3x/5 = 9/20
12x/20 = 9/20
12x= 9
x= 9/12 = 3/4
F)
x/5 =(x-3)/2
2x/10 = 5(x-3)/10
2x/10 = 5x-15/10
2x =5x-15
15 = 5x-2x
15 = 3x
x= 15/3 = 5
G)
7x -5x -10 = 2x -10
7x-5x-2x -10+10
0x=0