résoudre ses équations suivantes svp merci ​

Bonsoir,

a. 5x - 8 = 2x + 3

5x - 2x = 3 + 8

3x = 11

x = 11/3

b. 7x + 9 = 4x - 2

7x - 4x = - 2 - 9

3x = - 11

x = - 11/3

c. 9x - 11 = 13x + 5

9x - 13x = 5 + 11

- 4x = 16

x = - 16/4

x = - 4.