document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1121776>Question 1121776</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Write An equation for each ellipse.\r<BR>\n" );
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document.write( "Foci at (-3, -3), (7, -3); the point (2, -7) on ellipse </SPAN>\n" );
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document.write( "a = length of semi-major axis<BR>\n" );
document.write( "b = length of semi-minor axis<BR>\n" );
document.write( "c = distance from center to each focus<br><BR>\n" );
document.write( "The two foci are (-3,-3) and (7,-3); that means the center is (2,-3); that makes c=5.<br><BR>\n" );
document.write( "The point (2,-7) is on the ellipse; it has the same x coordinate as the center; that makes b=4.<br><BR>\n" );
document.write( "For an ellipse, <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;\" >, or <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=a%5E2+=+c%5E2%2Bb%5E2 ALIGN=MIDDLE  ALT=\"a%5E2+=+c%5E2%2Bb%5E2\"   DISABLED_style= \"max-width:90%; height:auto;\" >.  You know b and c, so you can determine a.<br><BR>\n" );
document.write( "Now you know a, b, and the center of the ellipse.  Plug them into the standard form of the equation. </SPAN>\n" );
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