Why do this problem?
The context is interesting and this can be an exercise in finding
distances using coordinates. This process, of repeatedly reflecting
the snooker table in its sides, occurs in many areas of advanced
mathematics and for a simple introduction see the article In
Space Do All Roads Lead Home?
Use the hint.
We know the ball bounces of the cushion at an equal angle so how do
we use this fact to find the right point on the cushion to aim