This was given in class to us
Equation of a Plane
From geometry, you learned that three distinct non-collinear points will determine a unique plane. Algebraically, the equation of the plane is given by Ax + By + Cz = D; thus, if the three distinct points were given, then we should be able to find the values of A, B, C, and D which will describe the equation of the plane passing through the points.
Suppose the points P(1, 2, 4), Q(-2, 2, -2), and S(2, 1, 3) are the three distinct points determining the plane PQS. Write the algebraic representation for the plane containing these points.
Your solution is due Wednesday, 3/18 by the beginning of class!
i don't exactly understand how to approach this problem