# Interesting Triangles Phenomenon

Creation of this resource was inspired by a problem that appears in the November 2021

*Mathematics Teachers' Journal*published by the Association of Mathematics Teachers of New York State (@AMTNYS). This problem was proposed by James M. Parks from SUNY (Potsdam, NY).## Given angle ADB and DBC are supplementary and AB = DC, how can we prove what is shown towards the end of this animation?

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