Is this a problem that can be solved?
Given the following information:
You are in a car going 35 miles per hour. You pass a tree on the side of the road and there is a person behind the tree. You can never see who it is because they are always behind the tree.
How fast is the person going?
For an actual problem, one could estimate the distance to the tree from the car as being 24 feet and the distance from the tree to the person as being 6 feet. But those are only estimates.
You also need to know the diamter of the tree trunk.
Then I make it the speed of the person when the distance between the tree and the car isis .