Nikolaos Dergiades, Antirhombi,
Forum Geometricorum, 14 (2014) 163--171.

Abstract. First we give the definition and some properties of the non-rhombus quadrilateral that we call antirhombus, that is circumscribed around a circle with center the centroid of the quadrilateral. Then we try to cut a triangle ABC with a line to form an antirhombus, we prove that there are three such lines forming with the sides of ABC an hexagon circumscribed around the incircle of ABC and then investigate their interesting configuration.

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