KnowraBrahmagupta's formulaLinked fromLinked fromThe 9 pages that link to Brahmagupta's formula, each with the reason it gives.All 9Broader topic 2Related 3Compared with 4Cyclic quadrilateralRelated: It gives the greatest possible area for a quadrilateral with fixed side lengths.QuadrilateralRelated: It gives the area from side lengths when the quadrilateral is cyclic.Ptolemy's inequalityRelated: Its cyclic setting shares the equality geometry behind Ptolemy's theorem.