document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1204257>Question 1204257</A>: <I><SPAN STYLE=\"word-break: break-all;\"> From a second-storey window directly across the street, the angle of elevation of the top of an office building in Makati is 57° 20' and the angle of depression of the base is 18° 10'. If the buildings are 38 m. apart, what is the height of the building? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #840397 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=840397\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <font color=black size=3><BR>\n" );
document.write( "57° 20' = 57 + (20/60) = 57.33333° approximately<BR>\n" );
document.write( "18° 10' = 18 + (10/60) = 18.16667° approximately\r<BR>\n" );
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document.write( "Diagram<BR>\n" );
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document.write( "The person's eye is located at point A.<BR>\n" );
document.write( "B is just across from A.<BR>\n" );
document.write( "C and D are the top and base of the other building.\r<BR>\n" );
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document.write( "Focus on triangle ABC.<BR>\n" );
document.write( "tan(angle) = opposite/adjacent<BR>\n" );
document.write( "tan(angle CAB) = BC/AB<BR>\n" );
document.write( "tan(57.33333°) = x/38<BR>\n" );
document.write( "x = 38*tan(57.33333°)\r<BR>\n" );
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document.write( "Now turn your focus to triangle ABD.<BR>\n" );
document.write( "tan(angle) = opposite/adjacent<BR>\n" );
document.write( "tan(angle DAB) = BD/AB<BR>\n" );
document.write( "tan(18.16667°) = y/38<BR>\n" );
document.write( "y = 38*tan(18.16667°)\r<BR>\n" );
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document.write( "The total height of CD is<BR>\n" );
document.write( "CD = CB + BD<BR>\n" );
document.write( "CD = x + y<BR>\n" );
document.write( "CD = 38*tan(57.33333°) + 38*tan(18.16667°)<BR>\n" );
document.write( "CD = 38*( tan(57.33333°) + tan(18.16667°) )<BR>\n" );
document.write( "CD = 71.73617\r<BR>\n" );
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document.write( "The building is roughly 71.736 meters tall.<BR>\n" );
document.write( "Round this approximate value however your teacher instructs.<BR>\n" );
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