parallel | | set of points in a plane that are the same distance from the center |

congruent | | exact location in space |

area | | angle that measures 90 degrees |

interior | | angle whose measures greater that 90 but less than 180 degrees |

pi | | line segment that passes through the center of a circle and has endpoint on the circle |

octagon | | triangle with two congruent sides |

heptagon | | line segment with one endpoint in the center of a circle and the other endpoint on the circle |

diameter | | line segment that joins two points on the circumference of a circle |

equilateral | | having same shape and same size |

corresponding | | angles formed by two lines entersected by a third line |

hexagon | | three-sided polygon |

vertex | | pair of opposite congruent angles formed by intersecting lines |

chord | | angle that measures less than 90 degrees |

rhombus | | object or structure looks the same after a specific change occurs |

pentagon | | number of square units needed cover a given surface |

perimeter | | eight-sided polygon |

obtuse | | distance around a circle |

isosceles | | matching two or more angles or polygons |

exterior | | quadrilateral with exactly one pair of parallel sides |

acute | | four-sided polygon |

symmetrical | | lines that cross at exactly one point |

scalene | | line that cuts across two or more parallel lines at different points |

trapezoid | | nine-sided polygon |

similar | | straight path that extends without end in opposite directions |

decagon | | having same shape but not necessarily the same size |

triangle | | ratio of circumference to the length of its diameter; 3.14 |

vertical | | six-sided polygon |

transversal | | point where two sides intersect on angle or polygon |

alternate | | distance around a polygon |

perpendicular | | parallelogram with all sides congruent |

line | | lines in a plane that do not intersect |

quadrilateral | | part of a line that starts in one point and continues forever |

nonagon | | angles on the outer sides of two lines intersected by a third line |

radius | | ten-sided polygon |

circumference | | five-sided polygon |

right | | triangle with three congruent sides |

ray | | triangle with no congruent sides |

circle | | lines that lie in different planes that are neither parallel or perpendicular |

skew | | lines that intersect to form right angles |

intersecting | | angles on the inner sides of two lines intersected by a third line |

point | | seven-sided polygon |