1. The problem statement, all variables and given/known data Find the equation of all planes containing the points P(2, -1, 1) and Q(1, 0, 0) 2. Relevant equations 3. The attempt at a solution I use PQ to get a vector, (-1, -1, 1). I some how need to use another vector so I can use the cross product to find the planes. So i let another point A(x, y, z) and find a vector PA, (x+1, y+1, z-1)? If i use the cross product i get (-z-y, z+x, 2-y+x) with a scalar equation of a(-z-y)+b(z+x)+c(2-y+x) = 0 I don't feel confident with my conclusion, is there a concept I'm misunderstanding about finding the planes?