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.Ptolemy's theoremCompared with: It also depends on cyclicity but determines area rather than relating diagonals and sides.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.