C est pour demain svp, le 18

a)
5x - 8 = 4
5x = 4 + 8
5x = 12
x = 12/5

b)
3x - 6 = 8 - 3x
3x + 3x = 8+ 6
6x = 14
x = 14/6 = 7/3

c)
6 - 2(3x + 4) = 8x - (5 - 6x)
6 - 6x - 8 = 8x - 5 + 6x
-6x - 8x - 6x = -5 - 6 +8
-20x = -3
x = 3/20 

a)
5x-8 = 4   =>   5x = 4 +8 = 12
x = 12/5

b)
3x - 6 = 8 -3x
6x = 8+6 = 14
x = 14/6 
x = 7/3

c) 
6 -2(3x +4 ) = 8x -(5-6x)
6- 6x - 8 = 8x -5 +6x
6-8 +5 = 6x +8x +6x
3 = 20x
x = 3/20