Question 276320
Multiply the first equation by -4. You get

8x-16y=0
You leave the second equation intact:
-8x+y=15

Now, add the equations:

-15y=15
This implies y=-1.

Put y=-1 into the first equation to get -2x-4=0 this implies x=-2.
You can verify that (-2,-1) works by substituting into the second equation:

16-1=15; 15=15.