I'm trying to solve a problem for work. Here's what I'm dealing with in generic terms: I've got two points, P1 = x1,y1 and P2 = x2,y2. Obviously I know the distance between those, lets call that d1. I'm trying to set find a third point called P3 = x3,y3. I'm given d2, the distance between x1,y1 and x3,y3, and d3, the distance between x2,y2, and x3, y3. Technically there's two possible answers, but I'll know which one to pick. This is really just a matter of finding the third point on a triangle, given two points and the length of each side. Obviously if d1 > d2 + d3 I don't have a solution, but I can handle that.