(2x+5)(x+3)=2x au carre-(3x+1)+(x-6)
(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
(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.