Perimeter of Rectangle

Perimeter = length + width + length + width

OR

Perimeter = 2 × length + 2 × width

Some perimeter problems involve solving for a missing dimension.

Use the given information to set up an equation and solve for the width.

Perimeter | = | length | + | width | + | length | + | width |

50 ft | = | 15 ft | + | width | + | 15 ft | + | width |

50 ft | = | 15 ft | + | 15 ft | + | width | + | width |

50 ft | = | 30 ft | + | width | + | width |

50 ft | = | 30 ft | + | 10 ft | + | 10 ft |

OR

Perimeter | = | 2 | × | length | + | 2 | × | width |

50 ft | = | 2 | × | 15 ft | + | 2 | × | width |

50 ft | = | 30 ft | + | 2 | × | width |

50 ft | = | 30 ft | + | 2 | × | 10 ft |

The width of the rectangle is 10 feet.