J' aurais besoin encore de l' aide pour ces équations :
a ) 5x + 3 = 2x + 12
b ) 7x - 6 = 9x - 8
c) x +9 = -3x - 11
d) 7x -7 = 5x + 2
e) 12x -5 = x - 27
a)5x-2x=12-3
3x=9
x=3
b)7x-9x=-8+6
-2x=-2
x=1
c)x+3x=-11+9
4x=2
x=1/2
d)7x-5x=7+2
2x=9
x=9/2
e)12x+x=-27+5
13x=22
x=22/13
a.
5x+3=2x+12
5x+3-2x=2x+12-2x
3x+3=12
3x+3-3=12-3
3x=9
x=9/3
x=3
b .
7x - 6 = 9x - 8
7x - 6-9x = 9x - 8-9x
-2x-6=-8
-2x-6+6=-8+6
-2x=-2
x=-2/-2
x=1
c.
x +9 = -3x - 11
x+9+3x=-3x+11+3x
4x+9=11
4x+9-9=11-9
4x=2
x=2/4
x=0.5
d.
7x -7 = 5x + 2
7x-7-5x=5x+2-5x
2x-7=2
2x-7+7=2+7
2x=9
x=9/2
x=4.5
e.
12x -5 = x - 27
12x-5-x=x-27-x
11x-5=-27
11x-5+5=-27+5
11x=-22
x=-22/11
x=-2
voilà... :)