A | B |

acute angle | an angle which measures less than 90 degress |

obtuse angle | an angle which measures more than 90 degrees |

scalene triangle | a triangle with no equal sides |

isosceles triangle | a triangle with two equal sides |

equilateral triangle | a triangle with three equal sides |

right triangle | a triangle with a right angle |

quadrilateral | a polygon with four sides |

square | a parallelogram with four equal sides and four right angles |

rhombus | a parallelogram with four equal sides and no right angles |

trapezoid | a quadrilateral with one set of parallel lines |

rectangle | a parallelogram with two sets of equal sides and four right angles |

parallelogram | a quadrilateral with two sets of parallel sides and no right angles |

hypotenuse | the side across from the right angle in a right triangle |

polygon | a closed plane figure with straight sides |

line segment | part of a line with a definite beginning and end |

parallel lines | lines which never intersect |

perpendicular lines | lines which intersect at a right angle |

right angle | an angle which measures exactly 90 degrees |

diameter | a line in a circle which measure from side to side through the center |