Okay: A pipe of negligible diameter is to be carried horizontally around a corner from a hallway 8 feet wide into a hallway 4 feet wide.

a) what is the maximum length that the pipe can have? and

b) if we set the pipe's diameter at 1 inch, how does this affect the problem?

This is beyond me. I set up a diagram and think I'm supposed to be finding the max L, when L= x+y, where x is the length of the pipe in the 8 foot hallway and y is the length of the pipe in the 4 foot hallway. After this, i don't know where to proceed. I think it needs trig or similar triangles perhaps. Please help? Thanks so much...