bonjour
A = 5a2-3a + 8 + 10a - 2a - 10
A = 5 a² + 5 a - 2
B = 6x - (-2x + 5x - 6) + (4x - x + 1)
b = 6 x + 2 x - 5 x + 6 + 4 x - x + 1
B = 6 x + 7
-4x + 10 = -8
- 4 x = - 8 - 10
- 4 x = - 18
x = 18/4 = 9 /2
2) 5x - 12 = 2x - 9
5 x - 2 x = - 9 + 12
3 x = 3
x = 1