Excircles Kissing a Central Circle

Problem

Triangle ABCABC has integer side lengths with AB=ACAB=AC. A circle ω\omega is centered at the incenter of ABC\triangle ABC. The excircle opposite to the side BCBC is internally tangent to ω\omega, while the excircles opposite to the sides ACAC and ABAB are externally tangent to ω\omega. Find the minimum possible perimeter of ABC\triangle ABC.

Answer

Solution

Difficulty9/10
Topicsplane geometry, Tangent Circle, Circles, Triangle Geometry

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