Hi Burr,

I'm not exactly clear on what your asking, you need to know 2 values of a right angle triangle to find the unknown, so if you have 2 known distances you can calculate the angle. If you have an angle and a distance you can calculate the unknown distance.
I've attached a trigonometry example sheet which shows the formulas used for the different knowns and unknowns.

Is this what you meant ?

Cheers
~Danny~