Cartesian quation of the plane passing through a point

[modern mountain]

I have a point of coordinates P(px,py,pz), how can I find the equation of a plane passing through this point?

[thorny gull]

you need a point and a normal to define a plane- there are an infinite number of planes which include point P. the normal is a line that is perpendicular to the plane- like the z axis is to the x,y plane.