Plane

The plane has length and width. The plane also refers to a hypothetical two-dimensional space of infinite extent; this use is used, for example, when describing tilings of the plane. Points on the plane can be shown using two coordinates, written as
(x,y)
. In analogue with Space.
== Objects on the Plane ==
=== List of Uniform Polygons ===
* Henagon
* Digon
* Triangle
* Square
* Pentagram
* Pentagon
* Hexagon
* Heptagon
* Octagon
* Nonagon
* Decagon
* ...
* Apeirogon
*
=== List of Curved Shapes ===
* Circle
* Semicircle
=== Flexagons ===
A Polygon which has 3 or more faces is called a flexagon
=== Polyominoes ===
Polyominoes are two-dimensional figures consisting of multiple squares fixed edge-to-edge. There are an infinite number of polyominoes, and the number of polyominoes increases with the amount of squares allowed.
== Coordinates on the Plane ==
There are two coordinate systems that can be used to define points on the plane - Cartesian coordinates, and polar coordinates.
Cartesian coordinates consist of two distances - the left-right distance from the origin, and the up-down distance from the origin. This is written as
(x,y)
. Cartesian coordinates where either x or y are fixed trace out an infinite line. Cartesian coordinates where both are fixed trace out a point, and where none are fixed trace out a plane. Polar coordinates consist of a distance and an angle - the overall distance from the origin, and the angle of the point from horizontal. This is written as
(x,\theta )
. Polar coordinates where x is fixed trace out a circle; polar coordinates where θ is fixed trace out an infinite line. Polar coordinates where both are fixed trace out a point, and where none are fixed trace out a plane. When converting from polar to Cartesian coordinates, the equations
x\cos { \theta } =x
and
x\sin{\theta } =y
can be used. When converting from Cartesian to polar coordinates, the equations
\sqrt { { x }^{ 2 }+{ y }^{ 2 } } =x 
and
\tan ^{ -1 }{ (\frac { y }{ x } ) } =\theta 
can be used.
== Dimension ==
Name: Polygon
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Next: Space
Category:List of 2nd dimension
Category:Dimensions