1. The problem statement, all variables and given/known data Let P, Q, and R be the vertices of a parallelogram with adjacent sides PQ and PR. Find the other vector S. P (2, 0 ,-1), Q (-2, 4, 1), R (3, -1, 0) 2. Relevant equations PR = QS PQ = RS 3. The attempt at a solution I took the two equations and solved both of them, getting (-1, 3, 2) for S by making the coordinates of S into x, y, and z and solving the equations. However, my answer doesn't seem to be correct. Why am I wrong? Thank you in advance.