The total distance the puck traveled before it reached Marshall is the sum of the distance it traveled before it hit the wall and the distance it traveled after it hit the wall. We know that the puck traveled 5 feet to the wall and 25 feet after it hit the wall, so the total distance it traveled is:
5 feet + 25 feet = 30 feet
Since the puck traveled this distance in a straight line from Lu to Marshall, the distance between Marshall and the wall of the rink is the same as the distance between Lu and the wall of the rink. Therefore, we can divide the total distance the puck traveled by 2 to find the distance between Marshall and the wall of the rink:
30 feet ÷ 2 = 15 feet
So Marshall is 15 feet from the wall of the rink.