document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1165021>Question 1165021</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The arch of a bridge forms the upper half of an ellipse. The arch is 6 meters above the 20-meter-wide river. Write an equation for the ellipse in which its major axis coincides with the water level. </SPAN>\n" );
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document.write( "Let the origin be at water level, halfway between the two ends of the bridge.<br><BR>\n" );
document.write( "The major axis is 20 meters, so the semi-major axis is 10.<br><BR>\n" );
document.write( "The height of the arch is 6 meters, so the semi-minor axis is 6.<br><BR>\n" );
document.write( "Plug the numbers into the standard form of the equation for an ellipse:<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( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x%5E2%2F10%5E2%2By%5E2%2F6%5E2+=+1 ALIGN=MIDDLE  ALT=\"x%5E2%2F10%5E2%2By%5E2%2F6%5E2+=+1\"   DISABLED_style= \"max-width:90%; height:auto;\" ><br><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x%5E2%2F100%2By%5E2%2F36+=+1 ALIGN=MIDDLE  ALT=\"x%5E2%2F100%2By%5E2%2F36+=+1\"   DISABLED_style= \"max-width:90%; height:auto;\" ><br><BR>\n" );
document.write( " </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );