olymmath

AIME 2025b Problem 5

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Suppose △ABC\triangle ABC has angles ∠BAC=84∘,∠ABC=60∘,\angle BAC = 84^\circ, \angle ABC=60^\circ, and ∠ACB=36∘.\angle ACB = 36^\circ. Let D,E,D, E, and FF be the midpoints of sides BC‾,AC‾,\overline{BC}, \overline{AC}, and AB‾,\overline{AB}, respectively. The circumcircle of △DEF\triangle DEF intersects BD‾,AE‾,\overline{BD}, \overline{AE}, and AF‾\overline{AF} at points G,H,G, H, and J,J, respectively. The points G,D,E,H,J,G, D, E, H, J, and FF divide the circumcircle of △DEF\triangle DEF into six minor arcs, as shown. Find DE^+2⋅HJ^+3⋅FG^,\widehat{DE}+2\cdot \widehat{HJ} + 3\cdot\widehat{FG}, where the arcs are measured in degrees. [asy] import olympiad; size(6cm); defaultpen(fontsize(10pt)); pair B = (0, 0), A = (Cos(60), Sin(60)), C = (Cos(60)+Sin(60)/Tan(36), 0), D = midpoint(B--C), E = midpoint(A--C), F = midpoint(A--B); guide circ = circumcircle(D, E, F); pair G = intersectionpoint(B--D, circ), J = intersectionpoints(A--F, circ)[0], H = intersectionpoints(A--E, circ)[0]; draw(B--A--C--cycle); draw(D--E--F--cycle); draw(circ); dot(A);dot(B);dot(C);dot(D);dot(E);dot(F);dot(G);dot(H);dot(J); label("AA", A, (0, .8)); label("BB", B, (-.8, -.8)); label("CC", C, (.8, -.8)); label("DD", D, (0, -.8)); label("EE", E, (.8, .2)); label("FF", F, (-.8, .2)); label("GG", G, (0, .8)); label("HH", H, (-.2, -1)); label("JJ", J, (.2, -.8)); [/asy]

Dataset text AIME 1983 to 2026. Quoted with source.

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