résoudre les équations : - 7 = x - 3 et elle : 7x = 21 -3x = 12 et : 5x = -3

-7 = x -3
-7 +3 = x
-4 = x

7x = 21
x = 21/7
x = 3

-3x = 12
x = 12/ -3
x = -4

5x = -3
x= -3/5
x = -0,6

- 7 = x - 3
x = - 7 + 3
x = - 4

7x = 21
x = 21/7
x = 3

5x = - 3
x = - 3/5
x = - 0,6