document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=32140>Question 32140</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Could you please help me with this problem.\r<BR>\n" );
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document.write( "Write the equation of an elipse given vertex (15,0) and focus(12,0) <BR>\n" );
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document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #18657 by </B><A HREF=/tutors/aboutme.mpl?userid=mukhopadhyay><B>mukhopadhyay(490)</B></A><img src=\"/images/stars/stars-10.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=mukhopadhyay><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=18657\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> There are two vertices of an ellipse, and they are equidistant from the center.<BR>\n" );
document.write( "The center of the ellipse having vertices at (-15,0) and (15,0) is (0,0).  The major axis is x-axis.<BR>\n" );
document.write( "Standard equation is:<BR>\n" );
document.write( "x^2/a^2 + y^2/b^2 = 1<BR>\n" );
document.write( "a=15 (distance between center and vertex)<BR>\n" );
document.write( "c=12 (distance between center and focus)<BR>\n" );
document.write( "c^2=a^2-b^2<BR>\n" );
document.write( "=>b^2=15^2-12^2=27*3=81<BR>\n" );
document.write( "=>b=9<BR>\n" );
document.write( "So, the equation of the ellipse is:<BR>\n" );
document.write( "x^2/225+y^2/81=1 </SPAN>\n" );
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