Respuestas

2012-07-10T01:52:01+02:00

x=-3y

2(-3y)-y=7

-6y-y=7

-7y=7

y=-1

 

x=-3y=-3(-1)=3     x=3

2012-07-10T01:55:56+02:00

Solución:

x+3y=0

x=-3y

-Reemplazamos "x" en "y":

2x-y=7

2(-3y)-y=7

-6y-y=7

-7y=7

   y= -1

 

x=-3y

x=-3(-1)

x=3