Hi! I'm new to these forums, and a grade 10 Flash programmer. I'm currently building a collision detection library, with which I currently have Lines and Circles. My problem is that I don't know how to get the intersection points between a circle and a line. I'm using mx+b for the line, in other words infinite lines. I already have intersection with the equation x^2 + y^2 = r^2 good to go, but I have no idea how to translate this into: (x - h)^2 + (y - k)^2 = r^2, in other words add coordinates to the intersection calculation. I only need the calculations up to the point where I can get A, B, and C variables for the quadratic formula (from then on it's simple plugging in). Any help what so ever is greatly appreciated! I just found these forums, and it seems as though I'll be in heaven from now on! P.