What is a nonagon?
A nonagon or 9-gon is a nine-sided polygon through nine internal angles that amount to 1260°. A nonagon is also called an enneagon. In countless ways, enneagon is a an ext accurate term, due to the fact that it offers Greek roots because that both that is prefix (ennea-, meaning nine) and also suffix (-gon, angled).
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Nonagons room rarely offered in many geometry texts, yet it is an intriguing shape, even if it is you study a consistent nonagon or an rarely often rare nonagon.
To be a nonagon or enneagon, the shape must have all this properties:It must be 2 dimensional (planar)It must use only nine heat segmentsIt need to close in an area
The nine line segments room the nonagons" sides, and they connect to form the nonagons" angles.
A nonagon has nine right sides of equal length. If the sides room all the very same length, then you have a regular nonagon. If the sides vary in length, climate you have actually an irregular nonagon.
If the sides are curved, the is no a nonagon.
Every nonagon has actually nine inner angles that amount to 1260°, and also the ripe exterior angles of a nonagon sum to 360°.
Every an easy nonagon (not complex) can have it"s interior separated into seven triangles.
You can discover the sum of internal angles by multiplying 7 × 180°, which is just how you gain 1260°.
Because every diagonal has actually 9 internal angles that connect, a nonagon has actually 27 diagonals.
A regular nonagon shape has 9 same sides and also 9 congruent angles. In a continuous nonagon, each interior angle procedures 140°.
A regular nonagon is a subtle and also beautiful design:
It is very nearly a circle, but not quite. The inner angles are each 140°. You have the right to verify this since 1260° ÷ 9 (angles) = 140°.
The central angle is 40° (which you can calculate by separating 360° by 9). This way you have the right to construct a constant nonagon through 7 isosceles triangles through two angle of 70° and one edge of 40°.
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Irregular nonagons have the right to have sides of different lengths and also interior angle of varying sizes. Yet, also odd shapes like these room nonagons:
A polygon v at least one internal angle higher than 180° is a concave polygon and constantly created an rarely often rare polygon.