I'm dealing with a problem that seems (to my uneducated mind) like it should be more or less straightforward, but for some reason I've been unable to find any help on forums that are geared towards high school and college level math. Please forgive me if the solution is obvious. If I know the lengths of the three edges of face A on a not-necessarily-regular tetrahedron, and I know the three angles formed at the vertex opposite face A (vertex P), how can I determine the other edges and angles of the tetrahedron? With this information it is simple to determine the angles on face A. After this I am at a loss on how to proceed. I have attempted unsuccessfully to substitute into the sine law equivaletent for tetrahedrons (that the product of the sines of the clockwise angles adjacent to a given face is equal to the product of the sines of the counterclockwise angles), and then solve for one of the unknown variables, however it seems that the unknown variable always cancels itself out. Any suggestions on how to approach this problem would be appreciated.