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GeometryHardOlympiad Geometry

Olympiad Geometry · Hard problem

In △ABC\triangle ABC, point DD is on AB‾\overline{AB} and point EE is on AC‾\overline{AC}. We know m∠ADE=(3x+5)∘m\angle ADE = (3x + 5)^\circ, m∠ABC=(4x−10)∘m\angle ABC = (4x - 10)^\circ, and m∠AED=58∘m\angle AED = 58^\circ. If DE‾∥BC‾\overline{DE} \parallel \overline{BC}, find m∠Am\angle A.