Sagot :
1)- x=5/4
2)- x= -3
3)- x= -3
4)- x= -5/2
5)- x=0
Explications étape par étape:
1)- 4x - 5=0
4x= 5
x= 5/4
2)- 5x +7 = -8
5x= -8 -7 = -15
x= -15/5 = -3
3)- -3x + 1 = - 6x - 8
-3x + 6x = - 8 - 1
3 x = -9
x = -3
4)- 2x -1 sur 4 = x -2 sur 3
3(2x -1) = 4 (x -2)
6x -3 = 4x -8
6x - 4x = -8 +3
2x = -5
x = -5/2
5)- -2(5x - 6 ) - (- 7x +3 ) = -2x +9
- 10x +12 +7x -3 = -2x +9
- 10x + 2x = +9 -12 +3 = 0
- 8x = 0
x = 0