Réponse:
7x + 10 - 2x = 2x + 35 - 2x
5x + 10 = 35
5x + 10 - 10 = 35 - 10
5x = 25
5x / 5 = 25 / 5
1x = 5
x = 5
Réponse :
9x - 12 = 3x + 6
9x - 3x = 12+6
6x = 18
x = 18/6
x= 3
