Since the two equations equal y, set them equal to each other.
x-1=-2x+5
From there, solve for x.
First get x on one side, by using the addition property of equality.
x-1=-2x+5
3x-1=5
Isolate x by adding 1.
3x=6
Lastly get x all by itself by dividing each side by 3.
x=2
You can now substitute your x-value, 2, into one of the equations (or both, if you wish; either one will result in the same answer.)
y=x-1
y=2-1
y=1
OR
y=-2x+5
y=-2(2)+5
y=-4+5
y=1
Final answer:
x=2 and y=1
Any questions or anything you would like me to clarify, feel free to ask :)