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What are  Polygons. Types of polygons
A polygon is a closed plane figure with straight
sides. like
triangles and squares.

Polygons are 2-dimensional shapes. They are made
of
line segments (straight lines), and the shape is
closed.

The
Vertex is endpoint where the two sides meet.
These figures are examples of polygons
Not a Polygon
(has curve line)
Not a Polygon
(open, not closed
Simple or Complex
A polygon is simple if it is described by a single,
non-intersecting boundary; otherwise it is said to be
complex.
A polygon is called regular if all its sides are of equal
length and all its angles are equal. Otherwise it is
irregular.
Simple Polygon
Complex Polygon
Regular or Irregular
examples of regular polygons
Names of Polygons
Concave or Convex
example of Irregular polygons
Complex polygon,
lines intersects.
Circle, not a polygon, no
straight sides.
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Polygons can be Convex meaning all angles (vertex) are facing out like
most of the Polygons above. Are they could be concave or non-convex
Polygons with one or more angles (vertex) pointing in. Like the one to the
right.
Example of a
concave or
nonconvex
Triangles and squares are two
examples of Regular Convex Polygons
Polygons can be   named by how many sides they have,
starting from the Triangle which has three sides.
> What are Polygons? Types of polygons < you are here
These figures are examples of non-polygons
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