Plane
From Simple English Wikipedia, the free encyclopedia
- Plane can also refer to airplane.
A plane is a perfectly flat surface extending in all directions. Try to imagine the ceiling of a room, only extended into all directions infinitely. A plane has two dimensions : length and width. All planes are flat surfaces. If a surface is not flat, it is called a curved surface.
In geometry, a plane is made up of an infinite number of lines (or points). It has no thickness.
A plane figure is part of a plane. It is named by the capital letters (e.g. A, B, C, ...X, Y, Z) that are put at its corners.
Mathematicians say two planes can be:
- Parallel = they never meet.
- Concurrent = they meet forming a line.
- Coincident = they are one and the same.