Réponses

2014-03-16T22:00:18+01:00
Bonsoir

 7x (2 - 5x ) - (3x -10 ) (3x +10)

14x - 35x² - (9x² +30x -30x -100)
14x -35x² -9x² -30x +30x +100
- 44x² +14x +100


2014-03-16T22:04:59+01:00
7x (2 - 5x ) - (3x -10 ) (3x + 10)
= 14x - 35x² - (9x² -30x +30x -100)
= 14x - 35x² - 9x² + 30x - 30x +100
= -44x² +14x + 100