It has

**four**equal sides and**four**right angles, each measuring 90 degrees. A regular nonagon is a nine-sided shape with equal sides and equal angles of**140**degrees each.Simply so, what is the sum of the interior angles of a regular Nonagon?

140°

What are the interior angles of a 9 sided polygon?

The General Rule

Shape | Sides | Sum of Interior Angles |
---|---|---|

Octagon | 8 | 1080° |

Nonagon | 9 | 1260° |

.. | ||

Any Polygon | n | (n-2) × 180° |

What is the interior and exterior angle of a regular Nonagon?

The sum of the exterior angles of any

**polygon**is 360 degrees. Therefore to find the measure of one exterior angle of any regular (all angles are congruent)**polygon**, divide 360 by the number of angles. In the**case**of a regular nonagon, the measure of one exterior angle is 40 degrees: 360 / 9 = 40 degrees.