[SOLVED] Differential Equation Geometry/Word Problem Help!

Hi everyone, I'm currently having trouble mentally grasping this question I have:

**Find the equation of the curve that goes through (1,3) for which any tangent and the line from the origin to the point of contact make with the ordinate a triangle having area A.**

I have been trying several approaches to this, but to no avail. I assume it can be set up as a first-order differential equation of some sort. I've defined the curve as *a*, the tangent line as *b*, and the line from the point of tangency to the origin as *c*. I also defined a random point along the curve (alpha, beta). Thus,

EDIT: The area of the triangle, A, could also be found with one of the following:

I have verified that, in fact, .

Any insight would be greatly appreciated!