Solve by substitution:
4x - y = 5
4x + 4y = -4 ---> (divide by 4) ---> x + y = -1
Now, we have:
4x - y = 5
x + y = -1
Solve the first equation for y: 4x - y = 5
-y = -4x + 5
y = 4x - 5
Substitue this into the second equation: x + y = -1
x + (4x - 5) = -1
5x - 5 = -1
5x = 4
x = 4/5
Substitue this value for x back into the equation: x + y = -1
4/5 + y = -1
y = -9/5