document.write( "Question 208755: In Triangle ABC, AD is a median.
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Algebra.Com's Answer #157878 by Edwin McCravy(20055)\"\" \"About 
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In Triangle ABC, AD is a median.
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document.write( "\"AB%5E2=BD%5E2%2BAD%5E2\" by the Pythagorean theorem\r\n" );
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document.write( "\"AC%5E2=DC%5E2%2BAD%5E2\" by the Pythagorean theorem\r\n" );
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document.write( "\"AB%5E2%2BAC%5E2=BD%5E2%2BDC%5E2+%2B+2AD%5E2\" because equals \r\n" );
document.write( "                 added to equals \r\n" );
document.write( "                 give equals.\r\n" );
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document.write( "\"BD=DC\" because Median AD bisects side BC\r\n" );
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document.write( "\"AB%5E2%2BAC%5E2=DC%5E2%2BDC%5E2+%2B+2AD%5E2\"  Substituting DC for BD\r\n" );
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document.write( "\"AB%5E2%2BAC%5E2=2DC%5E2%2B+2AD%5E2\"   Combining like terms.\r\n" );
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document.write( "Edwin
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