document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=19984>Question 19984</A>: <I><SPAN STYLE=\"word-break: break-all;\"> There is the square ABCD. Trace a line between corner A and midpoint E of side DC. Trace another line between corner A and point F of side DC such that AF equals AB+FC. Prove that angle DAE is half of angle FAB. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #9649 by </B><A HREF=/tutors/aboutme.mpl?userid=Paul><B>Paul(988)</B></A><img src=\"/images/stars/stars-11.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Paul><IMG SRC=http://www.algebra.com/images/aboutme-small.gif BORDER=0 alt=\"About Me\" VALIGN=MIDDLE></A>&nbsp;<IMG SRC=http://www.algebra.com/images/nopicture.jpg><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=9649\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\">       ____e___  <BR>\n" );
document.write( "    D|x      x|C<BR>\n" );
document.write( "     |        |f<BR>\n" );
document.write( "     |        |  (Go on \"Show soucre\" to see the answer}<BR>\n" );
document.write( "    A|y______y|B\r<BR>\n" );
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document.write( "<DAE = <FAB<BR>\n" );
document.write( "Comment: First draw your diagram we know that <DAE and <FAB both equal 90degress = 180degrees. And we know that the whole square equals 360degrees.<BR>\n" );
document.write( "Label one side x and the other y. So it is 2x+2y=360\r<BR>\n" );
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document.write( "Proof: Lets say we want to proof that <DAE is equal to 90, because if we can proof this we will know that <FAB will equal 90. =180<BR>\n" );
document.write( "       In <DAE, DA=AE, so <DAE=<DEA. Since the sum of right angles in a square is 90. <BR>\n" );
document.write( "in <ABCD, (2x)+(y)+(y+45)=360<BR>\n" );
document.write( "                    2x+2y=180<BR>\n" );
document.write( "                      x+y=90<BR>\n" );
document.write( "In <FAB x+y = 90<BR>\n" );
document.write( "       45+45+<FAB=180<BR>\n" );
document.write( "        <FAB = 90<BR>\n" );
document.write( "Now if you do that to same throughout DAF is also 90 degrees  <BR>\n" );
document.write( " <BR>\n" );
document.write( "Now if 90 + 90 =180 And the middle of these two angles is 180 degrees. Then <DAF equals <FAB\r<BR>\n" );
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document.write( " </SPAN>\n" );
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