document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1161844>Question 1161844</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Find, in standard form, the equation of: \r<BR>\n" );
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document.write( "The ellipse with vertices at (1,-1) and (7,-1) and foci at (4+/- √5,-1) </SPAN>\n" );
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document.write( "The major axis is horizontal, so the general equation is<br><BR>\n" );
document.write( "<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;\" ><br><BR>\n" );
document.write( "The center is (h,k)<BR>\n" );
document.write( "a is the semi-major axis<BR>\n" );
document.write( "b is the semi-minor axis<BR>\n" );
document.write( "c is the distance from the center to each focus<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=c%5E2+=+a%5E2%2Bb%5E2 ALIGN=MIDDLE  ALT=\"c%5E2+=+a%5E2%2Bb%5E2\"   DISABLED_style= \"max-width:90%; height:auto;\" ><br><BR>\n" );
document.write( "The given information gives us, immediately or with very little work, (h,k) = (4,-1), a = 3, and c = sqrt(5).<br><BR>\n" );
document.write( "Use the known values of a and c to determine b; then you will have all you need to write the equation.<br><BR>\n" );
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