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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