document.write( "Question 1120495: Given regular hexagon ABCDEF,, with Centre O and sides of length 12. Let G be the midpoint of BC. Let H be the midpoint of DE. AH intersects EB at J and FG intersects EB at K..Find JK.
\n" ); document.write( "Hint given in question ::: draw auxiliary lines HG and DA.\r
\n" ); document.write( "\n" ); document.write( "Thanks for any help .
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Algebra.Com's Answer #737154 by greenestamps(13200)\"\" \"About 
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\n" ); document.write( "I didn't see any use in the suggested auxiliary line segments HG and DA....

\n" ); document.write( "Perhaps there is a clever way to solve the problem using them; my solution is not very difficult.

\n" ); document.write( "Consider the regular hexagon with the center O at (0,0), with sides AB and DE horizontal; A in quadrant III, B in quadrant IV, D in quadrant I, and E in quadrant II. Then the coordinates of the vertices of the hexagon are

\n" ); document.write( "\"A%28-6%2C-6%2Asqrt%283%29%29\"
\n" ); document.write( "\"B%286%2C6%2Asqrt%283%29%29\"
\n" ); document.write( "\"C%2812%2C0%29\"
\n" ); document.write( "\"D%286%2C6%2Asqrt%283%29%29\"
\n" ); document.write( "\"E%28-6%2C6%2Asqrt%283%29%29\"
\n" ); document.write( "\"F%28-12%2C0%29\"

\n" ); document.write( "Then the two midpoints in the problem have coordinates

\n" ); document.write( "\"G%289%2C-3%2Asqrt%283%29%29\"
\n" ); document.write( "\"H%280%2C6%2Asqrt%283%29%29\"

\n" ); document.write( "Now triangles HJE and AJB are similar, with the ratio of similarity 1:2 because of the lengths of the bases EH (length 6) and AB (length 12). Since the height of the hexagon is 12*sqrt(3), we can determine that the y coordinate of point J is 2*sqrt(3). (It is 1/3 of the way from side DE -- y value 6*sqrt(3) -- and side AB -- y value -6*sqrt(3).)

\n" ); document.write( "So we can determine that the coordinates of J are \"J%28-2%2C2%2Asqrt%283%29%29\".

\n" ); document.write( "The exact same similarity exists between triangles BKG and EKF, leading us to the coordinates of K as \"K%282%2C-2%2Asqrt%283%29%29\".

\n" ); document.write( "Then, making JK the hypotenuse of a right triangle, the Pythagorean Theorem (or the observation that we have a 30-60-90 right triangle, with legs 4 and 4*sqrt(3)) gives us the length of JK as 8.
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