A | B |

a line dividing a shape into two matching halves | line of symmetry |

a six-sided figure | hexagon |

a polygon with all sides and angles congruent | regular ploygon |

a quadrilateral with opposite sides parallel | parallelogram |

a simple closed figure fromed by three or more sides | polygon |

a ruler or any object with a straight side | staightedge |

the point where two edges of a polygon intersect | vertex |

the most common unit of measure for an angle | degree |

an angle whose measure is between 0 and 90 degrees | acute angle |

an angle whose measure is between 90 and 180 degrees | obtuse angle |