Lhuiler's (1782 AD) Formula

Doshnamdvayordvayor ghaatayutaanaam tisraanaam

vadhaat ekaikonetarattraikyam catushkavadhabhajitam

Iabdha mulena yadvrttam vishkambhaardhena nirmitam

sarvam caturbhujakshetram tasminneva tisthtahathe

The three sums of the product of sides, taken two at a time are to be multiplied together and divided by the product of the sums of the sides taken three at a time and diminished by the fourth. If a circle is drawn with the square root of this quantity as radius, the whole quadrilateral will be situated inside it.

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