Réponse :
Bonjour
1 ) 4 x + 8 = 12
4 x = 12 - 8
4 x = 4
x = 1
2 ) 7 x + 5 = 14
7 x = 14 - 5
7 x = 9
x = 9/7
3 ) 8 x - 12 = 4 x - 5 x - 2
8 x - 4 x + 5 x = - 2 + 12
9 x = 10
x = 10/9
4 ) 2 x + 1 = 5 x - 3
2 x - 5 x = - 3 - 1
- 3 x = - 4
x = 4/3
Explications étape par étape
