Perpendicular planes are planes that intersect at a right angle.
Perpendicular planes and lines
If one plane contains a line that is perpendicular to another plane, these two planes are perpendicular to each other.
If a line is perpendicular to a plane, many perpendicular planes can be constructed through this line.
If a line is perpendicular to a plane, any lines in the plane that intersect it are perpendicular to it.