document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1149938>Question 1149938</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Find the equation of an ellipse satisfying the given conditions.<BR>\n" );
document.write( "Foci: (-2,0) and (2,0); length of major axis: 8 </SPAN>\n" );
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document.write( "The given foci mean the major axis is horizontal, and the center of the ellipse is at the origin, (0,0).  For an ellipse with those features, the equation is<br><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x%5E2%2Fa%5E2%2By%5E2%2Fb%5E2+=+1 ALIGN=MIDDLE  ALT=\"x%5E2%2Fa%5E2%2By%5E2%2Fb%5E2+=+1\"   DISABLED_style= \"max-width:90%; height:auto;\" ><br><BR>\n" );
document.write( "a is the semi-major axis; b is the semi-minor axis.<BR>\n" );
document.write( "c is the distance from the center to each focus<BR>\n" );
document.write( "a, b, and c are related by the equation <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 tells you a=4 and c=2; from that you can determine b and thus write the equation.<br><BR>\n" );
document.write( " </SPAN>\n" );
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