Respuesta :

irspow
(-3x+3y=-9)-(-3x+y=7)

-3x+3x+3y-y=-9-7

2y=-16

y=-8, making -3x+3y=-9 become:

-3x+3(-8)=-9

-3x-24=-9

-3x=15

x=-5

So the solution to this system of equations is the point (-5, -8)