1. The problem statement, all variables and given/known data Find a parametric equation of each of the following planes: d) The plane in R4 containing the points P: (1,1,-1,2), Q: (2,3,0,1), and R: (1,2,2,3) 3. The attempt at a solution I found vector PQ <1,2,1,-1> and vector PR <0,1,3,1> My next thought was to find a vector orthogonal to those two (cross product PQ x PR) and then use that as my normal vector, and choose a point. Then my answer would be: <x,y,z,m> + t*normal vector. The problem is that I don't know how to take the cross product in 4 dimensions. I have read that it can only be taken in 3D and 7D ....but I'm rather lost as to how to find this plane's equation. Any help is thoroughly appreciated.