Answer: Attached to the post.
Explanation:
First, label points A and B--given as (3, -3) and (3, 1) respectively. Now connect the points to form line segment AB.
We need to reflect this line segment over the line y = x. To visualize this easier, let's draw line y = x. Two coordinates on this line is (1, 1) and (0, 0). Plot these points and connect them to form line y = x.
Finally, we need to reflect line segment AB over y = x. Imagine the line y = x is a mirror and reflect the line segment AB over it. In my diagram, line segment A'B' is the answer.