document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1206021>Question 1206021</A>: <I><SPAN STYLE=\"word-break: break-all;\"> 10. Given:  triangle  ABC below. \r<BR>\n" );
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document.write( "AB = 5\r<BR>\n" );
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document.write( "AC = 8\r<BR>\n" );
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document.write( "BC = 6\r<BR>\n" );
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document.write( "A.  Find m∠A in the triangle.\r<BR>\n" );
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document.write( "B.  Find the area of the triangle.\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 #843196 by </B><A HREF=/tutors/aboutme.mpl?userid=ikleyn><B>ikleyn(52925)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=ikleyn><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=ikleyn><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=843196\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> 10. Given:  triangle  ABC below. \r<BR>\n" );
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document.write( "AB = 5<BR>\n" );
document.write( "AC = 8<BR>\n" );
document.write( "BC = 6\r<BR>\n" );
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document.write( "A.  Find m∠A in the triangle.\r<BR>\n" );
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document.write( "B.  Find the area of the triangle.<BR>\n" );
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document.write( "(A)  Use the cosine law for the side \"a\" opposite to angle A\r\n" );
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document.write( "         <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=a%5E2 ALIGN=MIDDLE  ALT=\"a%5E2\"   DISABLED_style= \"max-width:90%; height:auto;\" > = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=b%5E2+%2B+c%5E2+-+2bc%2Acos%28A%29 ALIGN=MIDDLE  ALT=\"b%5E2+%2B+c%5E2+-+2bc%2Acos%28A%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >,  a = BC = 6;  b = AC = 8;  c = AB = 5:\r\n" );
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document.write( "         <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=6%5E2 ALIGN=MIDDLE  ALT=\"6%5E2\"   DISABLED_style= \"max-width:90%; height:auto;\" > = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=8%5E2+%2B+5%5E2+-+2%2A8%2A5%2Acos%28A%29 ALIGN=MIDDLE  ALT=\"8%5E2+%2B+5%5E2+-+2%2A8%2A5%2Acos%28A%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >.\r\n" );
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document.write( "     It gives  cos(A) = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%288%5E2+%2B+5%5E2+-+6%5E2%29%2F%282%2A8%2A5%29 ALIGN=MIDDLE  ALT=\"%288%5E2+%2B+5%5E2+-+6%5E2%29%2F%282%2A8%2A5%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=53%2F80 ALIGN=MIDDLE  ALT=\"53%2F80\"   DISABLED_style= \"max-width:90%; height:auto;\" > = 0.6625;\r\n" );
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document.write( "                   A = arccos(0.6625) = 48.51 degrees = 48 degrees and 31 minutes  (rounded).    <U>ANSWER</U>\r\n" );
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document.write( "(B)  Use the Heron's formula\r\n" );
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document.write( "         area of a triangle = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=sqrt%28s%2A%28s-a%29%2A%28s-b%29%2A%28s-c%29%29 ALIGN=MIDDLE  ALT=\"sqrt%28s%2A%28s-a%29%2A%28s-b%29%2A%28s-c%29%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >,\r\n" );
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document.write( "                               where \"s\" is semi-perimeter = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%285%2B8%2B6%29%2F2 ALIGN=MIDDLE  ALT=\"%285%2B8%2B6%29%2F2\"   DISABLED_style= \"max-width:90%; height:auto;\" > = 9.5 units.\r\n" );
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document.write( "         area of the triangle = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=sqrt%289.5%2A%289.5-5%29%2A%289.5-6%29%2A%289.5-8%29%29 ALIGN=MIDDLE  ALT=\"sqrt%289.5%2A%289.5-5%29%2A%289.5-6%29%2A%289.5-8%29%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > = 14.98 square units  (rounded).    <U>ANSWER</U>\r\n" );
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document.write( "Solved.\r<BR>\n" );
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