Answer:
Subtract y from first one
Add y to second one so:
x =8-y
x =2+y
For the first one, find 8 on the Y axis and mark a point. Then go down right and down one. Mark another point. Connect the dots.
For the second one, find 2 on the Y axis and mark a point. Go up and right and up one.
Mark another point. Connect the points.
Hope this helps