KnowraParallelogramLinked fromLinked fromThe 11 pages that link to Parallelogram, each with the reason it gives.All 11Broader topic 4Related 2Narrower topic 2Compared with 3Parallelogram lawBroader topic: For geometric vectors, the identity says the squared diagonals sum to the squared side lengths multiplied by two.Van Aubel's theoremBroader topic: Its paired side vectors make the center relationships especially transparent.Euler's quadrilateral theoremBroader topic: Its diagonals share a midpoint, reducing the theorem to the parallelogram law.British flag theoremBroader topic: The squared-diagonal identity extends from rectangles to all parallelograms.