It's easiest to isolate either x or y in one of the equations. Taking the first one, we can subtract 2x from each side to give:
-y = 16 - 2x or y = 2x -16
Then, knowing what y is in terms of x, we can substitute it into the second equation:
-x + 2(2x -16) = -8
-x + 4x -32 = -8
3x = 24
x = 8.
Now we can put x back into either of the equations to find y:
y = 2x - 16
y = 2(8) - 16
y = 0
Therefore, x is 8 and y is 0.