document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=43302>Question 43302</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Find the equation for the hyperbola described: <BR>\n" );
document.write( "Asymptotes y=x and y=-x; foci (-4,0) and (4,0. Thank you for your help! </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #28330 by </B><A HREF=/tutors/aboutme.mpl?userid=stanbon><B>stanbon(75887)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=stanbon><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=28330\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Find the equation for the hyperbola described: <BR>\n" );
document.write( "Asymptotes y=x and y=-x; foci (-4,0) and (4,0).\r<BR>\n" );
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document.write( "General Form: x^2/a^2 - y^2/b^2 = 1<BR>\n" );
document.write( "Foci= (c,0)=(4,0) implies that c=4<BR>\n" );
document.write( "Note that c^2=a^2+b^2<BR>\n" );
document.write( "So, 16=a^2+b^2<BR>\n" );
document.write( "Asmptote equation is y=(b/a)x<BR>\n" );
document.write( "But you are told y=x; so, b/a =1, and therefore b=a<BR>\n" );
document.write( "So, 16=a^2+a^2=2a^2<BR>\n" );
document.write( "Then a^2=b^2=8\r<BR>\n" );
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document.write( "EQUATION:<BR>\n" );
document.write( "x^2/8 - y^2/8 = 1\r<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H. </SPAN>\n" );
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