A | B |

edge | a straight line where 2 faces meet |

corner | the place where 2 or more edges meet |

plane figure | figures that are flat |

line | something that is straight, continues in both directions, and does not end |

line segment | the part of a line between two points, called endpoints |

congruent | figures that are the same size and shape |

symmetry | when two parts of a figure match when the figure is folded in half |

line of symmetry | the line along the fold that makes a figure symmetrical |

perimeter | the distance around a figure |

area | the number of square units needed to cover the surface of a figure |

volume | the number of cubic units needed to fill a solid figure |

pictograph | a type of graph that has a key which tells how many each picture stands for |