Similar Metric Characterizations of Tangential and Extangential Quadrilaterals
نویسندگان
چکیده
We prove five necessary and sufficient conditions for a convex quadrilateral to have an excircle and compare them to similar conditions for a quadrilateral to have an incircle.
منابع مشابه
More Characterizations of Tangential Quadrilaterals
In this paper we will prove several not so well known conditions for a quadrilateral to have an incircle. Four of these are different excircle versions of the characterizations due to Wu and Vaynshtejn.
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