A list of the more important polygons is given below. A polygon is a 2D shape that consists only of straight sides. The name of the type of polygon depends on the number of sides.

A regular polygon has sides of equal length, and a triangle and rectangle have special names when these polygons are regular.

Sides | Name | Regular |

3 | Triangle | Equilateral triangle |

4 | Quadrilateral | Square |

5 | Pentagon | |

6 | Hexagon | |

7 | Heptagon | |

8 | Octagon | |

9 | Nonagon | |

10 | Decagon |

What is the name of a regular 3-sided polygon?

Note that the only regular triangle is an equilateral triangle.

Answer: Equilateral Triangle

If a 20p piece had straight edges, what type of polygon would it be?

A 20p piece has seven edges.

Answer: Heptagon

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