XYZ Coordinates to Earth Plot

OK, update.
I was able to convert to XYZ coordinates, thx. As I'm most familiar with Pythagoras I decided to solve some triangles, no problem.

Then, I then decided to cross-check some answers to be sure I was on the right track. Using the sin function at different angles I ended up with a set of 'negative' radians and angles.

Even I know the 3 angles of a right triangle should add to 180, the 90 plus the two opposite angles. If you ignore the negative value, the two opposite angles add up to 90 degree which is perfect for right triangle.

Question is, what do I do about the negative values for radians and angles? Is this an absolute value issue?

SAT EXB 1.JPG
SAT EXB 2.JPG