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equal circumradii, diagonals of quadr. (Kyiv City Olympiad 2003 9.4)

Source:

June 27, 2021
geometryparallelogramrhombusinradius

Problem Statement

The diagonals of a convex quadrilateral divide it into four triangles. The radii of the circles circumscribed around these triangles are equal. Can such a property have a quadrilateral other than: a) parallelogram, b) rhombus?
(Sharygin Igor)