Ok what you have to do is get one variable in the two equations equal but opposite to each other. You already have that in y in the first one and -y in the second. Sometimes you would have to do some manipulation to get there.
Next, add the two together:
4x+y=-5 + 2x-y=-1 ---—-------- 6x=-6 x-1
Now plug in the -1 for x in one of the formulas above: 4(-1)+y=-5 solve for y -4+y=-5 y=-5+4 y=-1
