document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1167019>Question 1167019</A>: <I><SPAN STYLE=\"word-break: break-all;\"> 	A whispering gallery has a semielliptical ceiling that is 9 m high and 30 m long. How high is the ceiling above the two foci?  Also, find the distance of the focus from the center, equation of the ellipse, and answer to the problem.  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #791655 by </B><A HREF=/tutors/aboutme.mpl?userid=greenestamps><B>greenestamps(13203)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=greenestamps><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=greenestamps><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=791655\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <br><BR>\n" );
document.write( "The major axis is 30 feet and horizontal; the semi-minor axis is 9 feet and vertical.  So the equation is<br><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x%5E2%2F15%5E2%2By%5E2%2F9%5E2+=+1 ALIGN=MIDDLE  ALT=\"x%5E2%2F15%5E2%2By%5E2%2F9%5E2+=+1\"   DISABLED_style= \"max-width:90%; height:auto;\" ><br><BR>\n" );
document.write( "a=15 is the semi-major axis; b=9 is the semi-minor axis; the distance from the center to each focus is c, where <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=c%5E2+=+a%5E2-b%5E2 ALIGN=MIDDLE  ALT=\"c%5E2+=+a%5E2-b%5E2\"   DISABLED_style= \"max-width:90%; height:auto;\" ><br><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=c%5E2=15%5E2-9%5E2+=+225-81+=+144 ALIGN=MIDDLE  ALT=\"c%5E2=15%5E2-9%5E2+=+225-81+=+144\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=c+=+12 ALIGN=MIDDLE  ALT=\"c+=+12\"   DISABLED_style= \"max-width:90%; height:auto;\" ><br><BR>\n" );
document.write( "The height of the ceiling above each focus is the y value when x=c=12.<br><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=144%2F225%2By%5E2%2F81=1 ALIGN=MIDDLE  ALT=\"144%2F225%2By%5E2%2F81=1\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=y%5E2%2F81+=+81%2F225 ALIGN=MIDDLE  ALT=\"y%5E2%2F81+=+81%2F225\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=y%5E2=81%5E2%2F15%5E2 ALIGN=MIDDLE  ALT=\"y%5E2=81%5E2%2F15%5E2\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=y+=+81%2F15+=+27%2F5 ALIGN=MIDDLE  ALT=\"y+=+81%2F15+=+27%2F5\"   DISABLED_style= \"max-width:90%; height:auto;\" ><br><BR>\n" );
document.write( "ANSWERS:<BR>\n" );
document.write( "The height of the ceiling above each focus is 27/5 = 5.4m.<BR>\n" );
document.write( "Each focus is 12m from the center.<BR>\n" );
document.write( "The equation of the ellipse is <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x%5E2%2F225%2By%5E2%2F81=1 ALIGN=MIDDLE  ALT=\"x%5E2%2F225%2By%5E2%2F81=1\"   DISABLED_style= \"max-width:90%; height:auto;\" ><br><BR>\n" );
document.write( " </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );