Explications étape par étape:
1) x = 7/3. x = 0
2) x = - 5 x = 0
3) x = 2 x = 1/8
4) x = 3/5 x = - 3/5
5) x = 3. x = - 11
6) x = - 1/11. x = 7/13
7) x = 1/4. x = 1
8) x = 12/7. x = 3/2
