Hey, I need some help with this VERY basic trig/geometry problem. I just had my first trig class yesterday and we got this problem that is fairly basic, yet I can't seem to be able to do it without more advanced trig. We haven't learned anything with sin, cosin, or tangent yet and although I've already learned that in another class we're supposed to be able to solve this in a very basic way. Here's the problem:

An astronomical object has an actual diameter of 128 km and an apparent size of 24'16" as viewed from earth. How far is this object from earth?

So, I converted 24'16" into DD format and got .40444444 (with the last four repeating). I assume that the diagram should look something like this:

math

How should I find the lengths of the sides? Am I just going about this completely wrong? I wish we were allowed to use more advanced techniques but there's got to be a way to do this without them, or he wouldn't have assigned it. Thanks in advance.