Paris Pamfilos, Triangles with given incircle and centroid,
Forum Geometricorum, 11 (2011) 27--51.
Abstract. In this article we study the set of triangles sharing a common incircle and a common centroid. It is shown that these triangles have their vertices on a conic easily constructible from the given data. It is also shown that the circumcircles of all these triangles are simultaneously tangent to two fixed circles, hence their centers lie also on a conic.
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