Octagon – Definition with Examples An octagon is a polygon made up of 8 sides. It has eight angles. Octagon = Octa + gon where octa means eight and gon means sides.

Is an octagon a regular polygon Why or why not?

A regular octagon has eight congruent angles and eight congruent sides. Any polygon that does not have all congruent sides is an irregular polygon. Irregular polygons can still be pentagons, hexagons and nonagons, but they do not have congruent angles or equal sides. Here are some examples of irregular polygons.

Why is it called a polygon?

The word polygon comes from the Greeks, like most terms in geometry, which they invented. It simply means many (poly) angles (gon). A polygon can’t have any curves or any gaps or openings in its shape.

Is a hexagon a polygon?

In geometry, a hexagon (from Greek ἕξ, hex, meaning “six”, and γωνία, gonía, meaning “corner, angle”) is a six-sided polygon or 6-gon. The total of the internal angles of any simple (non-self-intersecting) hexagon is 720°.

Is a pentagon a polygon?

In geometry, a pentagon (from the Greek πέντε pente meaning five and γωνία gonia meaning angle) is any five-sided polygon or 5-gon. The sum of the internal angles in a simple pentagon is 540°. A pentagon may be simple or self-intersecting. A self-intersecting regular pentagon (or star pentagon) is called a pentagram.

Is an octagon always a regular polygon?

Regular and Irregular Octagon When an octagon has all equal sides and equal angles, then it is defined as a regular octagon. But if it has unequal sides and unequal angles, it is defined as an irregular octagon. A regular octagon is a closed shape with sides of equal length and interior angles of the same measurement.

What is not a regular polygon?

An irregular polygon is any polygon that is not a regular polygon. It can have sides of any length and each interior angle can be any measure. They can be convex or concave, but all concave polygons are irregular since the interior angles cannot all be the same.

How do you know if a polygon is regular or irregular?

Regular shapes have sides that are all equal and interior (inside) angles that are all equal. Irregular shapes have sides and angles of any length and size.

What are the properties of an octagon?

The word nonagon comes from the Latin word “nona”, meaning nine, and “gon”, meaning sides. So it literally means “nine sided shape”. Nonagons are also called enneagon, which comes from the Greek word “enneagonon”, which means “nine corners”.

What is a 10 sided shape called?

In geometry, a decagon (from the Greek δέκα déka and γωνία gonía, “ten angles”) is a ten-sided polygon or 10-gon. The total sum of the interior angles of a simple decagon is 1440°. A self-intersecting regular decagon is known as a decagram.

How do you describe a polygon?

A polygon is any shape made up of straight lines that can be drawn on a flat surface, like a piece of paper. Such shapes include squares, rectangles, triangles and pentagons but not circles or any other shape that includes a curve.

What is a polygon in math definition?

polygon, In geometry, any closed curve consisting of a set of line segments (sides) connected such that no two segments cross. The simplest polygons are triangles (three sides), quadrilaterals (four sides), and pentagons (five sides).

What is a polygon with 4 sides called?

Definition: A quadrilateral is a polygon with 4 sides. Definition: A parallelogram is a quadrilateral where both pairs of opposite sides are parallel. We use the symbol to represent a parallelogram.