How to compute triangle base/altitude intersection

Hi,

Hope you can help me solve this problem.

Suppose I have a triange ABC. I have altitude passing through vertice
C, and it intersects line AB or extension of line AB at point D.

Given coordinates of points A, B, and lengths of line segments AC, BC,
how would you calculate coordinates of point D?

I do have a way to compute it, but I just can't shake away this feeling
that it is not very efficient.

Any help will be appreciated.
Balabek.

.

Relevant Pages