Réponses

2013-06-05T17:36:31+02:00
A) 2+3x=8
3x=8-2
3x=6
x=6/3=2

B) 6x+1=-11
6x=-11-1
6x=-12
x=-12/6=-3

C) 105=-25x+30
105-30=-25x
75=-25x
x=-75/25=-3

x+3=18
x=18-3
x=15
2013-06-05T17:38:07+02:00

2 +3x = 8

3x = -2 +8

3x = +6

x = 6/3

x = 2

 

6x +1 = -11

6x = -1 -11

6x = -12

x = -12/6

x = -2

 

105 = -25x +30

+25x = -105 +30

+25x = -75

x = -75/25 = -15/5 = -3

 

 

x + 3 = 18

x = -3 +18

x = 15