## What is a nonagon?

A **nonagon** or **9-gon** is a nine-sided polygon through nine internal angles that sum to 1260°. A nonagon is likewise called one **enneagon**. In plenty of ways, enneagon is a much more accurate term, since it uses Greek roots for both the prefix (*ennea-, *meaning nine) and also suffix (-*gon, *angled).

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Nonagons space rarely used in many geometry texts, however it is an intriguing shape, whether you research a consistent nonagon or an irregular nonagon.

## Nonagon shape

To it is in a nonagon or enneagon, the shape must have actually all these properties:

It should be 2 dimensional (planar)It should use just nine line segmentsIt need to close in an areaThe nine heat segments are the nonagons" sides, and also they attach to form the nonagons" angles.

### Nonagon sides

A nonagon has actually nine right sides of same length. If the sides room all the same length, then you have a constant nonagon. If the sides differ in length, climate you have an irregular nonagon.

If the sides space curved, the is not a nonagon.

### Nonagon angles

Every nonagon has actually nine internal angles that sum to 1260°, and the ripe exterior angle of a nonagon sum to 360°.

Every basic nonagon (not complex) have the right to have it"s interior separated into 7 triangles.

You can uncover the amount of inner angles by multiplying 7 × 180°, i m sorry is how you acquire 1260°.

### Nonagon diagonals

Because every diagonal has actually 9 inner angles that connect, a nonagon has actually 27 diagonals.

## Regular nonagon

A consistent nonagon shape has actually 9 same sides and 9 congruent angles. In a continual nonagon, each internal angle steps 140°.

A consistent nonagon is a subtle and beautiful design:

It is an extremely nearly a circle, yet not quite. The inner angles room each 140°. You have the right to verify this because 1260° ÷ 9 (angles) = 140°.

The central angle is 40° (which you can calculate by separating 360° through 9). This method you have the right to construct a constant nonagon v 7 isosceles triangles v two angle of 70° and also one edge of 40°.

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## Irregular nonagon

Irregular nonagons can have political parties of various lengths and interior angles of differing sizes. Yet, even odd shapes prefer these room nonagons:

A polygon through at the very least one interior angle greater than 180° is a **concave polygon** and constantly created an irregular polygon.