Bonjour !
1)
6 - x = 13
6 - x + x = 13 + x
6 = 13 + x
13 + x - 13 = 6 - 13
x = -7
2)
4x - 2 = 10
4x - 2 + 2 = 10 + 2
4x = 12
4x/4 = 12/4
x = 3
3)
5x + 2 = 8x - 3
5x + 2 - 5x = 8x - 3 - 5x
2 = 3x - 3
3x - 3 + 3 = 2 + 3
3x = 5
3x/3 = 5/3
x = 5/3
4)
2(3b + 7) = 4(-2b + 1)
2*3b + 2*7 = 4*(-2b) + 4*1
6b + 14 = -8b + 4
6b + 14 + 8b = -8b + 4 + 8b
14b + 14 = 4
14b + 14 - 14 = 4 - 14
14b = -10
14b/14 = -10/14
b = -5/7
5)
6x - 3 = -2x + 5
6x - 3 + 2x = -2x + 5 + 2x
8x - 3 = 5
8x - 3 + 3 = 5 + 3
8x = 8
8x/8 = 8/8
x = 1
J'espère t'avoir aidé. Bon courage !
