Réponses

2013-05-13T20:33:07+02:00

(2x+5)(x+3) = 2x²-(3x+1)+(x-6)

2x²+6x+5x+15=2x²-3x-1+x-6

2x²+11x+15=2x²-2x-7

11x+2x+15+7=0

13x+22=0

13x=-22

x=13/22

 

2013-05-13T20:39:06+02:00

(2x + 5) (x + 3) = 2x² - (3x + 1) + (x + 6)

2x * x + 2x * 3 + 5 * x + 5 * 3 = 2x² - 3x - 1 + x + 6

2x² + 6x + 5x + 15 = 2x² - 2x + 5

2x² + 11x + 15 = 2x² - 2x + 5

2x² + 11x - 2x² + 2x = 5 - 15

13x = -10

x = -10

       13

 

Je crois que c'est ça. :3

 

PS : * = fois.