I need some help with spherical triangles. I am looking for the lengths of the sides of a spherical triangle given that all the angles. One being 90 degrees and the other 2 angles being 50 and 70 degrees. I don't even know how to go about solving this. I know there are 4 formulas for solving these tyle of problems the sine formula, the cosine formula, the polar cosine formula, and the cotangent formula. I also saw something called Napiers formula where you might use a pentagon to show the relationship of angles to sides so maybe I can find an answer with that. I have no idea where to begin to sove this, nor can I find a single example to follow. Please Help!