Question 153926
1.{{{4(x-y)=-12}}}
2.{{{4(x+y)=-20}}}
Divide both sides of both equations by 4.
1.{{{x-y=-3}}}
2.{{{x+y=-5}}}
Now add the two equations together, to cancel out y, and solve for x.
1.{{{(x-y)+(x+y)=-3-5}}}
{{{2x=-8}}}
{{{x=-4}}}
Using eq. 2,
{{{x+y=-5}}}
{{{-4+y=-5}}}
{{{y=-1}}}
.
.
.
(x,y)=(-4,-1)