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**remettub** If I know the lengths of the three edges of face A on an irregular 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?

In the image, the known elements are sides SQ, QR and RS, and angles SPQ, QPR, and RPS. The three angles on face A (SQR, SRQ, and QSR) can be easily found. What I'm after is one of the angles adjacent to face A (such as PQS) and/or the length of one of the missing edges (such as PQ).