Again I don't know what equation to use to solve this. Help please
Here is what we know:
- a spotlight on the ground shines on a wall 14 metres away
- a man 2 m tall walks from the spotlight toward the building at a spped of 1.8 m/s
Question: How fast is the length of his shadow on the building decreasing when he is 5 metres from the building?
I am leaving the computer for tonight but if you can lay out the steps of what I need to do to solve this I would appreciate it.
Thanks in advance