# Incenter Circle

Geometry Level 5

Let $$ABC$$ be a triangle, with $$AB=11$$ and $$AC=7$$, and let $$I, B_1, C_1$$ respectively be the incenter, the intersection between the side $$AC$$ and the internal bisector $$BI$$ of $$\angle ABC$$ and the intersection between the side $$AB$$ and the internal bisector $$CI$$ of $$\angle ACB$$. Knowing that $$AB_1C_1I$$ are concyclic, and that $$BC=\sqrt{n}$$, find $$n$$.

Also try Centroid Circle

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