What ideas have you had so far?
You're guessing. You need to think geometrically here. You've got one point on the plane, and, given the equations you have, you could generate the equation for a line in the plane. But to write down the equation for a plane, you need a line normal, or perpendicular, to the plane. How can you get that line?
solved it
by following the example
http://answers.yahoo.com/question/in...7131929AAStpWu