What is a Polygon?

In this animated video I would like to talk about Polygons

Polygons are 2-dimensional closed shapes.

A closed shape does not have any openings, and all of the lines connect.

You can’t leave the inside of a closed shape without crossing a line.

Polygons have straight lines and do not have curves

A polygon has three parts.

Straight Lines

Vertices which are the point at which the lines intercept

Angles are formed by intercepting lines



There are several types of polygons

A regular polygon has equal lines and angles

An irregular does not have equals lines and angles



A concave polygon has one angle greater than 180 degrees

A convex polygon does not have any internal angles greater than 180 degrees



A simple polygon does not have any lines that cross over.

A complex polygon has at least one line that crosses over itself



Polygon names

Named after the number of sides and angles

Triangle 3 sides

Quadrilateral

Pentagon 5

Hexagon 6

Heptagon 7

Octagon 8

Nonagon 9

Decagon 10

Hendecagon 11

Dodecagon 12

After 12 sides it is acceptable to give the number of sides and then gon

For example 14 gon has 14 sides



You may also enjoy...

Polygon Song

https://www.youtube.com/watch?v=69lfT...



What is a polygon, and different shapes.

https://www.youtube.com/watch?v=dRtbC...

Leave a Comment geometry, moomoomath, octagon, polygon, shapes, triangle

What is a polygon?

In this video you will learn the properties of a polygon.

Keywords:

Polygons | Square | Rectangle | Trapezoid | Geometry | Properties

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Leave a Comment geometry, polygon, rectangle, square, trapezoid

Difference Convex and Concave Quadrilaterals

In this video, you will learn the difference between a convex quadrilateral and a concave quadrilateral.

A quadrilateral is a four-sided polygon, but what is a convex Quadrilateral?

Quadrilaterals come in different shapes and sizes, and many common shapes we encounter daily are quadrilaterals.

A few examples include,

square

rectangle

parallelogram 

rhombus

kite

Quadrilaterals can be further divided by the interior angle measurements.

A convex quadrilateral has interior angles 180 degrees or less. 

A concave quadrilateral has an interior angle measure greater than 180 degrees. Most common quadrilaterals are convex, and they do not have any interior angle measure greater than 180 degrees. 

CONVEX QUADRILATERALS

What is a concave quadrilateral?

A concave quadrilateral has a reflex interior angle measure. In other words, one interior angle measure is greater than 180 degrees.

CONCAVE QUADRILATERALS

A dart is one example of a concave quadrilateral.

A helpful method for memorizing the difference between these two types of quadrilaterals is to think of a cave for a concave quadrilateral. The reflex angle creates a cavity of a cave, which has an angle measure greater than 180 degrees.

Related Links

Isosceles Trapezoid

Quadrilaterals

1 comment 180 degree angle, concave quadrilateral, convex quadrilateral, four sided, geometric shapes, geometry, moomoomath, polygon, quadrilaterals, reflex angle

What is a trapezoid?

A trapezoid has two parallel sides and two non-parallel sides. and four straight lines.

In this video you will learn the properties of a trapezoid including the,

• number of sides
• area formula
• how many sides are congruent
• how many sides of a trapezoid are parallel

Leave a Comment geometry, math, moomoomath, polygon, shapes, trapezoid