document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=58585>Question 58585</A>: <I><SPAN STYLE=\"word-break: break-all;\"> 146. Height of a post. Betty observed that the lamppost in the front of her house cases a show of length 8 feet when the angle of inclination of the sun is 60 degrees.  How tall is the lamppost? (In a 30-60-90 right triangle, the side opposite 30 is one-half the length of the hypotenuse)\r<BR>\n" );
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document.write( "not sure how to solve  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #40133 by </B><A HREF=/tutors/aboutme.mpl?userid=Earlsdon><B>Earlsdon(6294)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Earlsdon><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=40133\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> You can use the Pythagorean theorem to solve this problem: <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=c%5E2+=+a%5E2+%2B+b%5E2 ALIGN=MIDDLE  ALT=\"c%5E2+=+a%5E2+%2B+b%5E2\"   DISABLED_style= \"max-width:90%; height:auto;\" > Where: c = the length of the hypotenuse and a & b are the lengths of the other two sides of the right triangle.<BR>\n" );
document.write( "Let's use a for the height of the lamp post. And, as you state in your problem, in a 30-60-90 triangle, the side opposite the 30-degree angle is half the length of the hypotenuse. So you can write:<BR>\n" );
document.write( "c = 2(8 ft) = 16 ft.\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%2816%29%5E2+=+8%5E2+%2B+a%5E2 ALIGN=MIDDLE  ALT=\"%2816%29%5E2+=+8%5E2+%2B+a%5E2\"   DISABLED_style= \"max-width:90%; height:auto;\" > Simplify and solve for a, the height of the lamp post.<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=256+-+64+=+a%5E2 ALIGN=MIDDLE  ALT=\"256+-+64+=+a%5E2\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=192+=+a%5E2 ALIGN=MIDDLE  ALT=\"192+=+a%5E2\"   DISABLED_style= \"max-width:90%; height:auto;\" > Take the square root of both sides.<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=13.86+=+a ALIGN=MIDDLE  ALT=\"13.86+=+a\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "The lamp post is 13.86 feet high (approximately) </SPAN>\n" );
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