document.write( "Question 43248: In triangle ABC, c = 10 and angle A = angle B = 40o. Find the length of the median to line segment AC \n" ); document.write( "
Algebra.Com's Answer #28280 by psbhowmick(878)\"\" \"About 
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In triangle ABC, BD is the median which bisects the side AC.
\n" ); document.write( "Drop a perpendicular from C on AB intersecting AB at E.\r
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\n" ); document.write( "\n" ); document.write( "In triangle ABC, < CAB = < CBA = \"40%5Eo\" and AB = 10 units.
\n" ); document.write( "As triangle ABC is isoscles, so the perpendicular dropped from the vertex on the opposite bisects the opposite side.
\n" ); document.write( "Hence, AE = BE = \"AB%2F2\" = \"10%2F2\" = 5 units.\r
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\n" ); document.write( "\n" ); document.write( "Now, in triangle AEC, < AEC is right angle.
\n" ); document.write( "So, \"AE%2FAC\" = cos(< CAE)
\n" ); document.write( "or \"5%2FAC+=+cos%2840%5Eo%29\"
\n" ); document.write( "or \"AC+=+5%2Fcos%2840%5Eo%29\"
\n" ); document.write( "or \"AC+=+5%2F0.839\"
\n" ); document.write( "or \"AC+=+6.527\"\r
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\n" ); document.write( "\n" ); document.write( "So, AD = \"1%2F2\"AC = \"6.527%2F2\" = 3.263 units.\r
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\n" ); document.write( "\n" ); document.write( "Now, consider triangle ADB.
\n" ); document.write( "Apply cosine formula
\n" ); document.write( "\"BD%5E2+=+AD%5E2+%2B+AB%5E2+-+2%2AAD%2AAB\"cos(< BAD)
\n" ); document.write( "or \"BD%5E2+=+3.263%5E2+%2B+10%5E2+-+2%2A3.263%2A10%2Acos%2840%5Eo%29\"
\n" ); document.write( "or \"BD%5E2+=+60.655\"
\n" ); document.write( "or \"BD+=+sqrt%2860.655%29\"
\n" ); document.write( "or BD = 7.788 units\r
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\n" ); document.write( "\n" ); document.write( "Thus, the length of the median to the line segment AC is 7.788 units.
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