# A Guide to the GRE/Quadrilaterals

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## Quadrilaterals[edit]

The angles of a quadrilateral add up to 360º. There are 6 key types:

Square | Rectangle | |
---|---|---|

Four equal, 90º angles | ✓ | ✓ |

Four equal sides | ✓ | ✗ |

Rhombus | Parallelogram | |
---|---|---|

Opposing sides are parallel | ✓ | ✓ |

Diagonal angles are equal | ✓ | ✓ |

Adjacent angles add up to 180º | ✓ | ✓ |

All four sides are equal | ✓ | ✗ |

**Trapezoid**

*One*set of parallel sides

**Kite**

- Two sets of adjacent equal sides