bonsoir

2 x - 2 = 4 + 7 x

2 x - 7 x = 4 + 2

- 5 x = 6

x = - 6 /5

7 x /2  = 2 /3 - 3 x

21 x /6  = 4/6 - 18 x /6

21 x + 18 x = 4

39 x = 4

x = 4/39

2 x +3 = x + 5 - 2 + x

2 x - x - x = 5 - 2 - 3

0 x = 0

tout nombre est solution