To do elimination, you need to get same coefficient before the variable
Multiply (-x-y = -11) by 4
-4x + 9y = -18
-4x - 4y = -44
Now subtract
13y = 26, y = 2
Plug in y = 2 for any of the two equation
-x - 2 = -11
-x = -9, x = 9
Solution: x = 9, y = 2