Answer:
Yes
Explanation:
Try the points and see:
(x, y) = (-1, 3) . . . . x + y = -1 + 3 = 2 . . . . yes
(x, y) = (3, -1) . . . . x + y = 3 + (-1) = 2 . . . yes
The remaining points lie on the line connecting these points, so they, too will be on the graph of that line.