document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=689067>Question 689067</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Can someone please help me find the vertices and foci of the ellipse 3x^2+7y^2=21.  I have vertices (0,sqrt -3) and (0, sqrt 3) and foci (0,2) and (0,-2) but not sure if it's right. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #425865 by </B><A HREF=/tutors/aboutme.mpl?userid=lwsshak3><B>lwsshak3(11628)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=lwsshak3><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=425865\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Can someone please help me find the vertices and foci of the ellipse <BR>\n" );
document.write( "3x^2+7y^2=21<BR>\n" );
document.write( "x^2/7+y^2/3=1<BR>\n" );
document.write( "This is an equation of an ellipse with horizontal major axis.<BR>\n" );
document.write( "Its standard form of equation: <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%28x-h%29%5E2%2Fa%5E2%2B%28y-k%29%5E2%2Fb%5E2=1 ALIGN=MIDDLE  ALT=\"%28x-h%29%5E2%2Fa%5E2%2B%28y-k%29%5E2%2Fb%5E2=1\"   DISABLED_style= \"max-width:90%; height:auto;\" >, a>b, (h,k)=(x,y) coordinates of center.<BR>\n" );
document.write( "center: 0,0)<BR>\n" );
document.write( "a^2=7<BR>\n" );
document.write( "a=&#8730;7<BR>\n" );
document.write( "vertices: (0±a,0)=(0±&#8730;7,0)=(-&#8730;7,0) and (&#8730;7,0)<BR>\n" );
document.write( "b^2=3<BR>\n" );
document.write( "c^2=a^2-b^2=7-3=4<BR>\n" );
document.write( "c=2<BR>\n" );
document.write( "foci:  (0±c,0)=(0±2,0)=(-2,0) and (2,0)<BR>\n" );
document.write( " </SPAN>\n" );
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