Angle Bisector | | If 3 sides of one triangle are congruent to three sides of a second triangle, then they are congruent. |

Square | | When 3 or more lines, rays or segments intersect in the same point. |

Rhombus | | Has a pair of congruent base angles. |

Kite | | ..is a quadrilateral if the parallel sides are the bases. |

Postulate | | Its diagonals are perpendicular |

Triangle Median | | ...if and only if it is a rombus and a rectangle |

Isosceles Trapezoid | | ...if two sides and the included angle of one triangle are congruent to two sides and the included angle of a second triangle, then the two triangles are congruent. |

Legs | | ...if two angles and the included side of one triangle are congruent to two angles and the included side of a second triangle, then the two triangles are congruent. |

Isosceles Trapezoid | | A parallelogram with four congruent sides. |

Trapezoid | | A parallelogram with four right angles. |

Kite | | When its opposite sides are congruent |

Kite | | ...if and only if its diagonals are congruent |

Side-Angle-Side | | A quadrilateral that has two pairs of consecutive congruent sides, but opposite sides are not congruent. |

Angle-Side-Angle | | Is a statement that can be proven. |

Rectangle | | Is a rule that is accepted without proof. |

Angle-Angle-Side | | ...is a quadrilateral with exactly one pair of parallel sides |

Rectangle | | Exactly one pair of opposite angles are congruent |

Concurrent Lines | | A segment from a vertex to the midpoint of the opposite side. |

Isosceles Trapezoid | | The nonparallel sides of a trapezoid |

Isosceles Trapezoid | | ...If and only if its diagonals are perpendicular. |

Theorem | | When the legs of a trapezoid are congruent. |

Rhombus | | ...if and only if it has four right angles |

Trapezoid | | The segment that connects the midpoints of its legs. |

Square | | When each pair of base angles is congruent. |

Side-Side-Side | | A quadrilateral with both pairs of opposite sides parallel |

Parelellogram | | A ray that divides an angle into two congruent adjacent angles. |

Rhombus | | A parallelogram with four congruent sides and four right angles |

Parallellogram | | ..if and only if its diagonals are congruent |

Trapezoid Midsegment | | ...if two angles and a non-included side of one triangle are congruent to two angles and the corresponding no-inclulded side of a second triangle, then the two triangles are congruent. |