Self-intersecting polygons, crossed polygons, or self-crossing polygons are
polygons some of whose
edges
Edge or EDGE may refer to:
Technology Computing
* Edge computing, a network load-balancing system
* Edge device, an entry point to a computer network
* Adobe Edge, a graphical development application
* Microsoft Edge, a web browser developed by ...
cross each other. They contrast with
simple polygons, whose edges never cross.
Some types of self-intersecting polygons are:
*the
crossed quadrilateral, with four edges
**the
antiparallelogram, a crossed quadrilateral with alternate edges of equal length
***the
crossed rectangle, an antiparallelogram whose edges are two opposite sides and the two diagonals of a
rectangle
In Euclidean plane geometry, a rectangle is a quadrilateral with four right angles. It can also be defined as: an equiangular quadrilateral, since equiangular means that all of its angles are equal (360°/4 = 90°); or a parallelogram containi ...
, hence having two edges parallel
*
Star polygon
In geometry, a star polygon is a type of non-convex polygon. Regular star polygons have been studied in depth; while star polygons in general appear not to have been formally defined, certain notable ones can arise through truncation operations ...
s
**
pentagram, with five edges
**
heptagram, with seven edges
**
octagram, with eight edges
**
enneagram
Enneagram is a compound word derived from the Greek neoclassical stems for "nine" (''ennea'') and something "written" or "drawn" (''gramma''). Enneagram may refer to:
* Enneagram (geometry), a nine-sided star polygon with various configurations
...
or nonagram, with nine edges
**
decagram Decagram may refer to:
* 10 gram, or 0.01 kilogram
The kilogram (also kilogramme) is the unit of mass in the International System of Units (SI), having the unit symbol kg. It is a widely used measure in science, engineering and commerce world ...
, with ten edges
**
hendecagram
In geometry, a hendecagram (also endecagram or endekagram) is a star polygon that has eleven vertices.
The name ''hendecagram'' combines a Greek numeral prefix, '' hendeca-'', with the Greek suffix ''-gram''. The ''hendeca-'' prefix derives f ...
, with eleven edges
**
, with twelve edges
See also
*
List of regular polytopes and compounds#Stars
*
Complex polygon
{{DEFAULTSORT:Self-intersecting polygons,
Geometric shapes
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