# British flag theorem (Rectangles)

## Description

Rectangle is any quadrilateral with four right angles. It can also be defined as an equiangular quadrilateral, since equiangular means that all of its angles are equal (360°/4 = 90°). The British flag theorem says that if a point P is chosen inside rectangle ABCD then the sum of the squared Euclidean distances from P to two opposite corners of the rectangle equals the sum to the other two opposite corners.

Related formulas## Variables

AP | The distance from P to the corner A (m) |

CP | The distance from P to the corner C (m) |

BP | The distance from P to the corner B (m) |

DP | The distance from P to the corner D (m) |