"cyclic" is referenced in the pages listed below.
The sum of the products of opposite sides of an inscribed (cyclic) quadrilateral are equal to the product of its diagonals.
Definition and properties of a quadrilateral inscribed in a circle. Sometimes called a cyclic quadrilateral.
A formula for finding the area of an inscribed (cyclic) quadrilateral when you know the lengths of the four sides.
Opposite pairs of interior angles of an inscribed (cyclic) quadrilateral are supplementary
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