document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=623384>Question 623384</A>: <I><SPAN STYLE=\"word-break: break-all;\"> please help me solve this problem: HEIGHT OF A PROBLEM: In traveling across flat land, you notice a mountain directly in front of you. Its angle of elevation (to the peak) is 3.5 degrees. After you drive 13 miles closer to the mountain, the angle of elevation is 9 degrees. Approximate the height of a mountain.  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #392112 by </B><A HREF=/tutors/aboutme.mpl?userid=Alan3354><B>Alan3354(69443)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Alan3354><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=Alan3354><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=392112\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> In traveling across flat land, you notice a mountain directly in front of you. Its angle of elevation (to the peak) is 3.5 degrees. After you drive 13 miles closer to the mountain, the angle of elevation is 9 degrees. Approximate the height of a mountain. <BR>\n" );
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document.write( "Make a triangle ABC, C is the mountain top, A the 1st point, B the 2nd point.<BR>\n" );
document.write( "Angle CAB = 3.5<BR>\n" );
document.write( "Angle CBA = 180 - 9 = 171 degs<BR>\n" );
document.write( "Angle BCA = 180 - (3.5 + 9) = 5.5 degs<BR>\n" );
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document.write( "Find the distance BC = side a<BR>\n" );
document.write( "Law of Sines:<BR>\n" );
document.write( "c/sin(C) = a/sin(A)<BR>\n" );
document.write( "a = c*sin(A)/sin(C) = 9*sin(3.5)/sin(5.5)<BR>\n" );
document.write( "a =~ 5.7325 miles<BR>\n" );
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document.write( "h = a*sin(180 - 171)<BR>\n" );
document.write( "h =~ 0.89676 mi<BR>\n" );
document.write( "h =~ 4735 feet<BR>\n" );
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