I believe I've figured out a and b, but I don't understand c
Consider the points A(1,2,0), B(1,0,1), C(0,1,-1) and D(1,0,-1)
a) Find the equation of the plane passing through the points A, B, C. Is the point D on this plane?
b)Find a parametric equation for the line passing through D which is perpendicular (the line) to the plane of the triangle ABC.
c) Find the equation of the plane passing through A and D, which is perpendicular to the plane of the triangle ABC. Note: Two planes are perpendicular if their normal vectors are perpendicular.
a)equation of the plane ABC is -3x+y+2z=-1 and D is not on the plane
b)equation of line perpendicular to plane:
and like I said, I have no idea what to do for c