document.write( "Question 1061271: In any triangle ABC, E is any point on altitude line segment AD. Prove that (AC)^2-(CE)^2= (AB)^2-(EB)^2 \n" ); document.write( "
Algebra.Com's Answer #676190 by ikleyn(52835)\"\" \"About 
You can put this solution on YOUR website!
.
\n" ); document.write( "In any triangle ABC, E is any point on altitude line segment AD. Prove that (AC)^2-(CE)^2= (AB)^2-(EB)^2
\n" ); document.write( "~~~~~~~~~~~~~~~~~~~~~~~~~~~~~\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "
\r\n" );
document.write( "0.  Make a sketch to follow my arguments.\r\n" );
document.write( "\r\n" );
document.write( "\r\n" );
document.write( "1.  From the triangle ADC:  \"abs%28DC%29%5E2\" = \"abs%28AC%29%5E2+-+abs%28AD%29%5E2\".\r\n" );
document.write( "\r\n" );
document.write( "    From the triangle EDC:  \"abs%28DC%29%5E2\" = \"abs%28CE%29%5E2+-+abs%28ED%29%5E2\".\r\n" );
document.write( "\r\n" );
document.write( "    It implies  \"abs%28AC%29%5E2+-+abs%28AD%29%5E2\" = \"abs%28CE%29%5E2+-+abs%28ED%29%5E2\".\r\n" );
document.write( "\r\n" );
document.write( "    Hence,      \"abs%28AC%29%5E2+-+abs%28CE%29%5E2\" = \"abs%28AD%29%5E2+-+abs%28ED%29%5E2\".   (1)\r\n" );
document.write( "\r\n" );
document.write( "\r\n" );
document.write( "2.  Similarly,\r\n" );
document.write( "    From the triangle ADB:  \"abs%28BD%29%5E2\" = \"abs%28AB%29%5E2+-+abs%28AD%29%5E2\".\r\n" );
document.write( "\r\n" );
document.write( "    From the triangle EDC:  \"abs%28BD%29%5E2\" = \"abs%28BE%29%5E2+-+abs%28ED%29%5E2\".\r\n" );
document.write( "\r\n" );
document.write( "    It implies  \"abs%28AB%29%5E2+-+abs%28AD%29%5E2\" = \"abs%28BE%29%5E2+-+abs%28ED%29%5E2\".\r\n" );
document.write( "\r\n" );
document.write( "    Hence,      \"abs%28AB%29%5E2+-+abs%28BE%29%5E2\" = \"abs%28AD%29%5E2+-+abs%28ED%29%5E2\".   (2)\r\n" );
document.write( "\r\n" );
document.write( "\r\n" );
document.write( "3.  From (1) and (2) you have \r\n" );
document.write( "\r\n" );
document.write( "    \"abs%28AB%29%5E2+-+abs%28BE%29%5E2\" = \"abs%28AC%29%5E2+-+abs%28CE%29%5E2\".\r\n" );
document.write( "\r\n" );
document.write( "\r\n" );
document.write( "It is what has to be proved.\r\n" );
document.write( "
\r
\n" ); document.write( "\n" ); document.write( "Solved.\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "
\n" ); document.write( "
\n" );