résolvez les equations suivantes 2x+1=5- x            x+3=5x+9              x/3+7=- x/6           4-5x=-3(x-8)

2x+1=5-x

2x+x=5-1

3x=4

x=4/3

x+3=5x+9

x-5x=9-3

-4x=6

x=6/-4

x=-1.5

x/3+7=-x/6

2x/6+42/6=-x/6

2x+42=-x

2x+x=-42

3x=-42

x=-42/3

x=-14

4-5x=-3(x-8)

4-5x=-3*x-3*(-8)

4-5x=-3x+24

-5x+3x=24-4

-2x=20

x=20/-2

x=-10