posted by Jessi .
A straight ladder is leaning against the wall of a house. The ladder has rails 4.50 m long, joined by rungs 4.800 m long. Its bottom end is on solid but sloping ground so that the top of the ladder is 3.400 m to the left of where it should be, and the ladder is unsafe to climb. You want to put a rock under one foot of the ladder to compensate for the slope of the ground.
What should be the thickness of the flat rock (in cm)?
This problem confuses me so much. I really don't even know where to begin. Does it have something to do with angular and translational quantities?