Bonjour, vous pouvez m'aider avec cet exercice svp ? Résoudre : (x = la lettre) 1) -5x - 6 -2 = -5x - 7 2) -x - 3 - x = -4x + 2 3) -7 - 4x = -5x - 1 4) -3 ( 4x

Bonjour,

1) -5x - 6 -2 = -5x - 7

-5x +5x = -7 +6+2

impossible:

0 = +1

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

-x+4x -x = 2 +3

2x = 5

x= 5/2 = 2,5

3) -7 - 4x = -5x - 1

-4x+5x  = -1 +8

x = 7

4) -3 ( 4x - 5 ) = 6x

-12x +15 = 6x

15 = 6x +12x

15 = 18x

x= 15/18

x = 5/6

5) - 2x - ( 4x + 7 ) = - 3x + ( 7x + 5 )​

-2x -4x -7 = -3x +7x +5

-7 -5 = -3x +7x+2x +4x

-12 =  10x

x = - 12/10

x = - 6/5