This is why I say that it is going to take some time to explain what I'm trying to accomplish. There is four sections to the drawing. The first is the text, the second is the portion of the drawing that looks like a mess. The two parell arcs represent a arched steal beam. I'm trying to come up with an equation so as to solve the plum cut of the beam at any point along 1/2 the periphery of the arc. The triangle that is formed by the beam depth and the unknown vertical cut, forms an oblique triangle, the oppsite side is not tangent to the arc. The only knowns are the beam depth which is 10 and the adjcent angle of 19.47 deg. I can sovle the right triangle with the angle an Hyp as well as the opp side, but I can sole the other angle of the oblique triangle since I don't have enough knowns. This is where I need help, I've stared so close at all the trees, that I don't see the forest anymore. I know that it is solvable, but I can't figure where the relatinships are to get me where I want to go. There is a lot more, but I hate typing so I guess I'll go with the flow as it comes along.