image | | The point where the three medians of a triangle intersect |

transitive property | | A shape that results from a transformation of a figure known as the preimage |

parallelogram | | The relationship between figures having the same shape and same size |

congruence | | A point at an end of a segment or a starting point of a ray |

square | | Lying in the same plane |

equilateral triangle | | A statement that is accepted as true without proof |

trapezoid | | A point where the edges of a figure intersect |

acute triangle | | A statement using "if and only if" |

hypothesis | | A polygon in which all angles are congruent |

vertex | | For any real number (a, a=a) |

angle bisector | | A line, ray, or segment that intersects two or more coplaner lines, rays, or segments, each at a different point |

centroid | | Abbreviation for "corresponding parts of congruent triangles are congruent" |

theorem | | A quadrilateral with one and only one pair of parallel sides |

conjecture | | A triangle with three acute angles |

coplanar | | Two angles in a plane that share a common vertex and a common side but have no interior points in common |

endpoint | | A statement that has been proven to be true deductively |

transversal | | A figure formed by two rays with a common endpoint |

biconditional | | A triangle in which all three sides are congruent |

acute angle | | The pharse following the word if in a conditional statement |

obtuse angle | | A quadrilateral with two pairs of parallel sides |

angle | | A quadrilateral with four congruent sides and four right angles |

reflexive property | | A ray that divides an angle into two congruent angles |

collinear | | An angle whose measure is greater than 90 degrees |

equilateral polygon | | A segment from a vertex to the midpoint of the opposite side in a triangle |

CPCTC | | Lying on the same line |

median | | For all real numbers (a,b, and c, if a=b and b=c then a=c) |

equiangular polygon | | A polygon in which all sides are congruent |

vertical angles | | The opposite angles formed by two intersectingg lines |

rectangle | | An angle whose measure is less than 90 degrees |

adjacent angles | | A quadrilateral with four right angles |

postulate | | A statement that is believed to be true |