Réponses

2014-04-09T18:11:04+02:00
(7x-3)²-25
=(4x)²-25
(16x-25. 16x-16=-25-16
x=-18
Meilleure réponse !
  • Utilisateur Brainly
2014-04-09T18:12:48+02:00
Exo 66  facto :

(7x-3-5)(7x-3+5)
(7x-8)(7x+2)

(7x-8)(7x+2) = 0
7x-8 = 0
7x = 8
x =8/7

7x+2 = 0
7x = -2
x =-2/7