An -sided Polygon in which the sides are all the same length and are symmetrically placed about a common center. The sum of Perpendiculars from any point to the sides of a regular polygon of sides is times the Apothem. Only certain regular polygons are ``Constructible'' with Ruler and Straightedge.

Regular Polygon | |

3 | Triangle |

4 | Square |

5 | Pentagon |

6 | Hexagon |

7 | Heptagon |

8 | Octagon |

9 | Nonagon |

10 | Decagon |

12 | Dodecagon |

15 | Pentadecagon |

16 | Hexadecagon |

17 | Heptadecagon |

18 | Octadecagon |

20 | Icosagon |

30 | Triacontagon |

**References**

Bishop, W. ``How to Construct a Regular Polygon.'' *Amer. Math. Monthly* **85**, 186-188, 1978.

© 1996-9

1999-05-25