A light on the ground is 30 feet away from a building. A 4 foot tall man is walking from the light to the building at a rate of 3 feet per second. He is casting a shadow on the side of the building. At what rate is his shadow shrinking when he is 5 feet from the building?
This is my figure:
Is this correct?
How do I solve this problem? I tried using similar triangles but couldn't succeed. Could someone explain this with a figure?
Modified figure: light is on the ground.