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MathNet 2016-part-01 — 184 problems (EN–VI) Question 77

Math Olympiad Vault · MathNet 2016-part-01 — 184 problems (EN–VI)

Question 77

In triangle $ABC$, the points $D$ and $E$ are the intersections of the angular bisectors from $C$ and $B$ with the sides $AB$ and $AC$. Points $F$ and $G$ on the extensions of $AB$ and $AC$ beyond $B$ and $C$ satisfy $BF = CG = BC$. Prove $FG \parallel DE$.