Bonjour, Équations :1) -1-3x=9+7x 2) 3+2x=4x-5 3) 1-4x=x-4 4) 7x-4=13+2x merci aux courageux.

1) -1-3x=7x+9
-10x=10
x=-1

2) 2x+3=4x-5
-2x=-8
x=4

3) -4x+1=x-4
-5x=-5
x=1

4) 7x-4=2x+13
5x=17
x=17/5

1) - 1 - 3x = 9 + 7x
- 3x - 7x = 9 + 1
- 10x = 10
x = - 10/10
x = - 1

2) 3 + 2x = 4x - 5
2x - 4x = - 5 - 3
- 2x = - 8
x = - 8 / (- 2)
x = 4

3) 1 - 4x = x - 4
- 4x - x = - 4 - 1
- 5x = - 5 
x = - 5 / (- 5)
x = 1

4) 7x - 4 = 13 + 2x
7x - 2x = 13 + 4
5x = 17
x = 17/5