Equation 1)  y=5x+11
Equation 2)  y+5x=1
Rearrange equation 1 so that (y) and (x) are on the same side.
1)  y-5x=11
2)  y+5x=1
Add equations together.
2y=12
Divide both sides by 2.
y=6
Plug in (y) for equation 1
(6)=5x+11
Subtract 11 from both sides.
-5=5x
Divide both sides by 5.
x=-1
(-1, 6)
~Hope I helped!~