Réponses

2013-05-20T00:29:31+02:00

{2x-12=5y

{4y=-5-3x

 

{2x=5y+12

{4y=-5-3x

 

{2x/2=5y/2+12/2

{4y=-5-3x

 

{x=2.5y+6

{4y=-5-3(2.5y+6)

 

{x=2,5y+6

{4y=-5-7.5y-18

 

{x=2,5y+6

{11.5y/11.5=-23/11.5

 

{x=2.5(-2)+6

{y=-2

 

{x=1

{y=-2