This is my problem: We have a triangle ABC, that has a right angle at the vertex C. First we draw the height v from the vertex C, the heigh v intersects the line AB in point D. Now we draw 2 lines from point D, x and y, one that is parallel with line AC, the other parallel with line CB. Now I have to prove that c*x*y=v^3

this is the photo:

I know the problem is relatively simple: (using the pythagorean theorem multiple times )it just requires equation solving but I'm really lazy/stupid so if I could get any hints or help that would be really great...