MathDB
Parabola Intersecting Triangle

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August 8, 2024
conicsparabolageometry2022

Problem Statement

Triangle ABCABC has side lengths AC=3AC = 3, BC=4BC = 4, and AB=5AB = 5. Let II be the incenter of ABC\triangle{ABC}, and let P\mathcal{P} be the parabola with focus II and directrix AC\overleftrightarrow{AC}. Suppose that P\mathcal{P} intersects AB\overline{AB} and BC\overline{BC} at points DD and EE, respectively. Find DI+EIDI+EI.