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 4Heron's formulaCompared with: It generalizes the same semiperimeter product pattern from triangles to cyclic quadrilaterals.Cyclic quadrilateralRelated: It gives the greatest possible area for a quadrilateral with fixed side lengths.BrahmaguptaBroader topic: It is his most celebrated geometric result and extends Heron’s triangle-area formula.Ptolemy's theoremCompared with: It also depends on cyclicity but determines area rather than relating diagonals and sides.QuadrilateralRelated: It gives the area from side lengths when the quadrilateral is cyclic.Indian mathematicsBroader topic: It is a notable geometric result within Brahmagupta’s mathematical work.Ptolemy's inequalityRelated: Its cyclic setting shares the equality geometry behind Ptolemy's theorem.Bretschneider's formulaCompared with: It is the cyclic-quadrilateral special case that Bretschneider's formula generalizes.Pitot theoremCompared with: It concerns cyclicity rather than tangency, giving a useful comparison of quadrilateral constraints.