A spotlight on the ground shines on a wall 12 m away. If a man 2 m tall walks from the spotlight toward the building at a speed of 1.6 m/s, how fast is the length of his shadow on the building decreasing when he is 4 m from the building?
We assume x shows the distance between the man and the building. Also let's ...
This shows how to find the rate of change of the length of a shadow on a building.