Réponses

2014-06-01T20:54:07+02:00
Bonsoir

3x +2 y = 850
2x +4 y = 1 100

-6x -4y = - 1 700
2x +4 y = 1 100

-4x = - 600
x = 150

450 + 2y = 850
2y = 850 - 450
2y = 400
y = 200

vérification
450 + 400 = 850