document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=821555>Question 821555</A>: <I><SPAN STYLE=\"word-break: break-all;\"> I am not understanding this problem whatsoever.  Please help.\r<BR>\n" );
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document.write( "Because of the curvature of the earth, the maximum distance \"D\" that you can see from the top of a tall building or from an airplane at height \"h\" is given by the function:\r<BR>\n" );
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document.write( "[ D(h)= sqrt( 2rh + h^2 ) ]\r<BR>\n" );
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document.write( "Where r=3960 mi is the radius of the Earth and \"D\" and \"h\" are the measured in miles.\r<BR>\n" );
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document.write( "(a) Find D(0.1) and D(0.2).<BR>\n" );
document.write( "(b) How far can you see from the observation deck of Toronto's CN Tower, 1135ft above ground?<BR>\n" );
document.write( "(c) Commercial aircraft fly an altitude of about 7 mi.  How Far can the pilot see?\r<BR>\n" );
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document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #494222 by </B><A HREF=/tutors/aboutme.mpl?userid=TimothyLamb><B>TimothyLamb(4379)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=TimothyLamb><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/cgi-bin/show-face.mpl?user=TimothyLamb><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=494222\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> ---<BR>\n" );
document.write( "the problem gives you this formula: <BR>\n" );
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document.write( "D(h)= sqrt( 2(3960)h + hh )<BR>\n" );
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document.write( "I added the parentheses only to make the formula clear<BR>\n" );
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document.write( "all you have to do is plug into the above formula the h values (in miles) given in the problem, and do the math on a calculator, so just do the following on a calculator:<BR>\n" );
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document.write( "a)<BR>\n" );
document.write( "D(0.1)= sqrt( 2(3960)0.1 + (0.1)(0.1) )<BR>\n" );
document.write( "D(0.2)= sqrt( 2(3960)0.2 + (0.2)(0.2) )<BR>\n" );
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document.write( "b)<BR>\n" );
document.write( "first convert h = 1135 feet to miles (1135 ft * 1/5280 miles/ft) then plug the resulting h into the formula above<BR>\n" );
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document.write( "c)<BR>\n" );
document.write( "D(7)= sqrt( 2(3960)7 + 7*7 )<BR>\n" );
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document.write( "you can do the math on a calculator<BR>\n" );
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document.write( "Solve and graph linear equations:<BR>\n" );
document.write( "https://sooeet.com/math/linear-equation-solver.php<BR>\n" );
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document.write( "Solve quadratic equations, quadratic formula:<BR>\n" );
document.write( "https://sooeet.com/math/quadratic-formula-solver.php<BR>\n" );
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document.write( "Solve systems of linear equations up to 6-equations 6-variables:<BR>\n" );
document.write( "https://sooeet.com/math/system-of-linear-equations-solver.php </SPAN>\n" );
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