document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=384082>Question 384082</A>: <I><SPAN STYLE=\"word-break: break-all;\"> What is the area of the circle if XY= 10 Ft? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #271900 by </B><A HREF=/tutors/aboutme.mpl?userid=Jk22><B>Jk22(389)</B></A><img src=\"/images/stars/stars-10.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Jk22><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/cgi-bin/show-face.mpl?user=Jk22><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=271900\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> XY is the equation for an hyperbola <BR>\n" );
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document.write( "It's known that one can pass from hyperbolic to euclidean geometry via usage of complex number : <BR>\n" );
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document.write( "let \r<BR>\n" );
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document.write( "X=a+ib<BR>\n" );
document.write( "Y=a-ib<BR>\n" );
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document.write( "then XY=a^2-aib+aib+b^2=a^2+b^2=10, hence it's a circle in the complex plane with radius sqrt(10)Ft. </SPAN>\n" );
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