document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1206872>Question 1206872</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A passenger on a boat at sea looks up to the top of a mountain, 350 m above sea level. The angle of elevation is 12°. After the boat sails towards the mountain, the angle of elevation is found to be 23°. How far did it sail towards the mountain? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #844571 by </B><A HREF=/tutors/aboutme.mpl?userid=math_tutor2020><B>math_tutor2020(3817)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=math_tutor2020><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=844571\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <font color=black size=3><BR>\n" );
document.write( "Answer: <font color=red>822.072210279 meters approximately</font><BR>\n" );
document.write( "Round this value however needed.\r<BR>\n" );
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document.write( "Explanation\r<BR>\n" );
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document.write( "Review this similar question<BR>\n" );
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document.write( "On that solution page I provide the derivation of this formula<BR>\n" );
document.write( "h = d*u*v/(u-v)<BR>\n" );
document.write( "where,<BR>\n" );
document.write( "h = height or altitude of the object<BR>\n" );
document.write( "d = distance between observation points<BR>\n" );
document.write( "u = tangent of larger angle<BR>\n" );
document.write( "v = tangent of smaller angle\r<BR>\n" );
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document.write( "We can easily solve for variable d.<BR>\n" );
document.write( "h = d*u*v/(u-v)<BR>\n" );
document.write( "h(u-v) = d*u*v<BR>\n" );
document.write( "d = h*(u - v)/(u*v)\r<BR>\n" );
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document.write( "Then plug in the following information<BR>\n" );
document.write( "h = 350<BR>\n" );
document.write( "u = tan(23)<BR>\n" );
document.write( "v = tan(12)<BR>\n" );
document.write( "and we should get,\r<BR>\n" );
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document.write( "h = d*u*v/(u - v)<BR>\n" );
document.write( "d = 350*(tan(23) - tan(12))/(tan(23)*tan(12))<BR>\n" );
document.write( "d = <font color=red>822.072210279 approximately</font><BR>\n" );
document.write( "Please make sure that your calculator is set to degrees mode.<BR>\n" );
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