bonjour
7 x - 8 = 2 x - 5
7/5 - 8 = 2/5 - 5
7/5 - 40/5 = 2/5 - 25/5
- 33 /5 ≠ - 23/5
donc 1/5 n'est pas solution
6 x + 50 = - 4 x + 7
- 25.2 + 50 = 16.8 + 7
24.8 ≠ 23.8 donc - 4.2 n'est pas solution
8 x + 11 = 2 x + 27
8 x - 2 x = 27 - 11
6 x = 16
x = 16/6 = 8/3
- 3 x - 22 = 7 x + 1
- 3 x - 7 x = 1 + 22
- 10 x = 23
x = - 23/10 = - 2.3
4 x + 15 = 5 x + 21
4 x - 5 x = 21 - 15
- x = 6
x = - 6
1.2 b - 4.6 = 5.3 b - 8.7
1.2 b - 5.3 b = - 8.7 + 4.6
- 4.1 b = - 4.1
b = 1
