Réponses

  • Utilisateur Brainly
2014-04-13T15:37:40+02:00
3x+2 = x²+2x-4

-x²+5x+6 = 25/4-(x-1/2)²

[5/2-(x-1/2)][5/2+(x-1/2)] = 0
(5/2-x+1/2)(5/2+x-1/2) = 0
(-x+3)(x+2) = 0

-x+3= 0
x = 3

x=2  =0
x = -2