bonjour j ai besoin d aide svp merci beaucoup

Réponse:

4x - 2 = 18

4x = 18 + 2

4x = 20

x = 20 : 4

x = 5

-2x + 5 = -7

-2x = 7 - 5

-2x = 2

x = 2 : -2

x = -1

7x - 4 = 8x - 11

7x - 8x = -11 + 4

-1x = -7

x = -7 : -1

x = 7

3(2x -4) = 4(2x -5)

6x - 12 = 8x -20

6x - 8x = -20 + 12

-2x = -8

x = -8 : -2

x = 4