bonjour
5 x+ 7 = 2 x- 2
5 x - 2 x = - 2 - 7
3 x = - 9
x = - 3
3 x + 2 = x - 10
3 x - x = - 10 - 2
2 x = - 12
x = - 6
2 x - 5 = 5 x + 1
2 x - 5 x = 1 + 5
- 3 x = 6
x = - 2
3 - 7 x = 3 x+ 2
- 7 x - 3 x = 2 - 3
- 10 x = - 1
x = 1/10
2 x - 1/3 = 1
6 x /3 = 3/3 + 1 /3
6 x = 4
x = 4/6 = 2 /3