document.write( "Question 251610: Given- Isosceles triangle ABC with segment Ab congruent to segment AC
\n" ); document.write( "line CD is perpendicular to AB.
\n" ); document.write( "Prove- Segment BC multiplied by segment BC is equal to two times segment AB multiplied by segment BD
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Algebra.Com's Answer #183873 by vksarvepalli(154)\"\" \"About 
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consider the triangle BCD which is a right angled triangle\r
\n" ); document.write( "\n" ); document.write( "now using Pythagoras theorem we get
\n" ); document.write( " \"BC%5E2=CD%5E2+%2B+BD%5E2\"------------1\r
\n" ); document.write( "\n" ); document.write( "now consider the triangle ACD which is also a right angled triangle\r
\n" ); document.write( "\n" ); document.write( "again using Pythagoras th.
\n" ); document.write( " \"AC%5E2=AD%5E2%2BCD%5E2\"------------2\r
\n" ); document.write( "\n" ); document.write( "but AB=AC (isosceles) \r
\n" ); document.write( "\n" ); document.write( "so substituting it in 2 we get
\n" ); document.write( " \"AB%5E2=AD%5E2%2BCD%5E2\"\r
\n" ); document.write( "\n" ); document.write( "but AB=AD+DB\r
\n" ); document.write( "\n" ); document.write( "so, \"%28AD%2BBD%29%5E2=AD%5E2%2BCD%5E2\"\r
\n" ); document.write( "\n" ); document.write( "i.e., \"BD%5E2%2BAD%5E2%2B2%2AAD%2ABD=AD%5E2%2BCD%5E2\"\r
\n" ); document.write( "\n" ); document.write( "on simplifying we get \"CD%5E2=BD%5E2%2B2%2AAD%2ABD\"\r
\n" ); document.write( "\n" ); document.write( "substituting the value of CD^2 in equation 1\r
\n" ); document.write( "\n" ); document.write( "\"BC%5E2=BD%5E2%2B2%2AAD%2ABD+%2B+BD%5E2\"\r
\n" ); document.write( "\n" ); document.write( "taking out BD common in the right hand side of the equation \r
\n" ); document.write( "\n" ); document.write( "\"BC%5E2=2%2ABD%2A%28AD%2BBD%29\"
\n" ); document.write( "but AD+BD=AB\r
\n" ); document.write( "\n" ); document.write( "therefore \"BC%5E2=2AB%2ABD\"
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