What is a nonagon?

A nonagon or 9-gon is a nine-sided polygon with nine interior angles that sum to 1260°. A nonagon is likewise referred to as an enneagon. In many type of means, enneagon is a much more specific term, because it provides Greek roots for both its presolve (ennea-, interpretation nine) and also sufsettle (-gon, angled).

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Nonagons are hardly ever offered in many geomeattempt messages, yet it is an intriguing shape, whether you research a continuous nonagon or an irregular nonagon.


Nonagon shape

To be a nonagon or enneagon, the form should have all these properties:

It have to be 2 dimensional (planar)It have to use just nine line segmentsIt must cshed in an area

The nine line segments are the nonagons" sides, and also they affix to form the nonagons" angles.


Nonagon sides

A nonagon has actually nine straight sides of equal length. If the sides are all the exact same size, then you have a continuous nonagon. If the sides vary in length, then you have an irregular nonagon.


If the sides are curved, it is not a nonagon.

Nonagon angles

Eextremely nonagon has nine interior angles that amount to 1260°, and the nine exterior angles of a nonagon amount to 360°.


Eexceptionally straightforward nonagon (not complex) have the right to have actually it"s inner divided into seven triangles.


You can discover the amount of interior angles by multiplying 7 × 180°, which is how you obtain 1260°.

Nonagon diagonals

Since eincredibly diagonal has actually 9 internal angles that affix, a nonagon has 27 diagonals.


Regular nonagon

A continual nonagon shape has 9 equal sides and 9 congruent angles. In a regular nonagon, each inner angle measures 140°.

A continuous nonagon is a subtle and beautiful design:


It is extremely virtually a circle, however not quite. The internal angles are each 140°. You have the right to verify this bereason 1260° ÷ 9 (angles) = 140°.

The main angle is 40° (which you have the right to calculate by separating 360° by 9). This indicates you deserve to construct a continuous nonagon with 7 isosceles triangles through 2 angles of 70° and also one angle of 40°.

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Irregular nonagon

Irconstant nonagons have the right to have sides of various lengths and also inner angles of varying sizes. Yet, also odd forms choose these are nonagons:


A polygon through at leastern one inner angle greater than 180° is a concave polygon and always produced an irconsistent polygon.