Réponses

2013-05-26T11:45:16+02:00
Meilleure réponse !
2013-05-26T11:47:50+02:00

  2x - 3y = -20

-8x - 3y = 12

 

(2x - 3y) - (-8x - 3y) = -20 - 12

2x + 8x = - 32

x = -3.2

 

-3y = -20 - 2x

-3y = -20 + 6.4

-3y = - 13.6

y = 13.6/3