OK, I need a bit of help with some Pythagorean Theorem here. I'll try and post a pic below, but here goes.

I'm making a lift kit for my camper. The camper is too short for my truck (all existing adjustments are maxed out). The existing frame is 6" tall. I intend to build a second frame 6" tall, then weld to the existing frame. I will have one leg at 12", the second leg with be 71". Using the theory of a^2 + b^2 = c^2 , that places 12^2+71^2=c^2. Or, 144+5041=5185^2. The square root of 5185 is 72". Am I looking at this correctly? I'm trying to calculate how much steel I'll need to buy to do this job.

Your use of the Pythagorean Theorem is correct, but to tell if you're using correctly in your case you'll need to show a diagram of your intended modification.

Mike

Thank you. I'll get photos and a better diagram this evening.