document.write( "Question 911998: In rectangle ABCD, a point M is selected inside the rectangle. If AM=4, BM=5, and CM=6, find the length of DM.
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Algebra.Com's Answer #553803 by Fombitz(32388)\"\" \"About 
You can put this solution on YOUR website!
Let the coordinates of A be (0,0).
\n" ); document.write( "Then B would be (0,xb), C would be (xc,yc), and D would be (xd,0).
\n" ); document.write( "Calculate the distance from each vertex to M.
\n" ); document.write( "AM:
\n" ); document.write( "\"%28x-0%29%5E2%2B%28y-0%29%5E2=16\"
\n" ); document.write( "1.\"x%5E2%2By%5E2=16\"
\n" ); document.write( "BM:
\n" ); document.write( "2.\"%28x-0%29%5E2%2B%28y-yb%29%5E2=25\"
\n" ); document.write( "CM:
\n" ); document.write( "3.\"%28x-xc%29%5E2%2B%28y-yc%29%5E2=36\"
\n" ); document.write( "DM:
\n" ); document.write( "4.\"%28x-xd%29%5E2%2By%5E2=%28alpha%29%5E2\" where \"alpha\" is the unknown distance.
\n" ); document.write( "First we can simplify since,
\n" ); document.write( "\"yb=yc\" and \"xc=xd\"
\n" ); document.write( "So then, for CM,
\n" ); document.write( "3.\"%28x-xc%29%5E2%2B%28y-yb%29%5E2=36\"
\n" ); document.write( "and for DM,
\n" ); document.write( "4.\"%28x-xc%29%5E2%2By%5E2=%28alpha%29%5E2\"
\n" ); document.write( "Substituting from 3 into 4.
\n" ); document.write( "\"%2836-%28y-yb%29%5E2%29%2By%5E2=%28alpha%29%5E2\"
\n" ); document.write( "Then substituting from 2,
\n" ); document.write( "\"36-%2825-x%5E2%29%2By%5E2=%28alpha%29%5E2\"
\n" ); document.write( "\"11%2B%28x%5E2%2By%5E2%29=%28alpha%29%5E2\"
\n" ); document.write( "Finally, substituting from 1,
\n" ); document.write( "\"11%2B16=%28alpha%29%5E2\"
\n" ); document.write( "\"alpha%5E2=27\"
\n" ); document.write( "\"alpha=sqrt%2827%29\"
\n" ); document.write( "\"DM=3sqrt%283%29\"
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