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Find <A_44 A_45 A_43

Source: 1978 AHSME Problem 28

June 18, 2014
AsymptoteAMC

Problem Statement

[asy] import cse5; size(180); pathpen=black; pair A1=(0,0), A2=(1,0), A3=(0.5,sqrt(3)/2); D(MP("A_1",A1)--MP("A_2",A2)--MP("A_3",A3,N)--cycle); pair A4=(A1+A2)/2, A5 = (A3+A2)/2, A6 = (A4+A3)/2; D(MP("A_4",A4,S)--MP("A_6",A6,W)--A3); D(A6--MP("A_5",A5,NE)--A4); //Credit to chezbgone2 for the diagram[/asy]
If A1A2A3\triangle A_1A_2A_3 is equilateral and An+3A_{n+3} is the midpoint of line segment AnAn+1A_nA_{n+1} for all positive integers nn, then the measure of A44A45A43\measuredangle A_{44}A_{45}A_{43} equals
<spanclass=latexbold>(A)</span>30<spanclass=latexbold>(B)</span>45<spanclass=latexbold>(C)</span>60<spanclass=latexbold>(D)</span>90<spanclass=latexbold>(E)</span>120<span class='latex-bold'>(A) </span>30^\circ\qquad<span class='latex-bold'>(B) </span>45^\circ\qquad<span class='latex-bold'>(C) </span>60^\circ\qquad<span class='latex-bold'>(D) </span>90^\circ\qquad <span class='latex-bold'>(E) </span>120^\circ