document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=647719>Question 647719</A>: <I><SPAN STYLE=\"word-break: break-all;\"> For altitudes h up to 10,000 meters, the density D of the earth's atmosphere (in kg/m3) can be approximated by the following formula:<BR>\n" );
document.write( "D=1.225-(1.12x10^-4)h+(3.24x10^-9)h^2\r<BR>\n" );
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document.write( "Approximate the altitude if the density of the atmosphere is 0.63 kg/m3. (Round to the nearest meter.) </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #406349 by </B><A HREF=/tutors/aboutme.mpl?userid=DrBeeee><B>DrBeeee(684)</B></A><img src=\"/images/stars/stars-11.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=DrBeeee><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=406349\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Set D = 0.63 and get<BR>\n" );
document.write( "(1) ah^2 + bh + c = 0<BR>\n" );
document.write( "When h is in km, we have<BR>\n" );
document.write( "a = 3.24 E-3<BR>\n" );
document.write( "b = -1.12 E-1<BR>\n" );
document.write( "c = 0.595<BR>\n" );
document.write( "Or<BR>\n" );
document.write( "a = 0.00324<BR>\n" );
document.write( "b = -0.112<BR>\n" );
document.write( "c = 0.595<BR>\n" );
document.write( "Using these simpler decimals we can easily apply the quadratic equation to determine the two roots of (1) as<BR>\n" );
document.write( "(2) h = abt 28, 6.5558 km<BR>\n" );
document.write( "The first root of ~28 is not a choice because it is out of the solution domain of the equation for the density D.<BR>\n" );
document.write( "Answer: The density of earth's atmosphere is 0.63 kg/m^3 at an altitude of 6,556 meters. </SPAN>\n" );
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