76

Part of 1990 IMO Longlists

Problems(1)

At least two non-congruence quadrilaterals - ILL 1990 ROM2

Source:

Prove that there exist at least two non-congruent quadrilaterals, both having a circumcircle, such that they have equal perimeters and areas.

geometrycircumcircleperimetercyclic quadrilateralgeometry proposed