document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=442956>Question 442956</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Find the area of Triangle ABC, if AB=6cm, AC=12cm, and the measure of angle A is 20 degrees. Express your answer to the nearest tenth of a square centimeter. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #305530 by </B><A HREF=/tutors/aboutme.mpl?userid=swincher4391><B>swincher4391(1107)</B></A><img src=\"/images/stars/stars-12.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=swincher4391><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=swincher4391><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=305530\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> We know that angle A is opposite BC.\r<BR>\n" );
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document.write( "Let's call side AB and side AC\r<BR>\n" );
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document.write( "We can find what cos(A) is since we know A = 20º\r<BR>\n" );
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document.write( "Let's use the law of cosines.\r<BR>\n" );
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document.write( "Let BC = a, AB = c , AC = b\r<BR>\n" );
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document.write( "a^2 = b^2 + c^2 - 2bc cos(20)\r<BR>\n" );
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document.write( "a^2 = 12^2 + 6^2 - 2(12)(6)cos(20)\r<BR>\n" );
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document.write( "a^2 = 144 + 36 - (144cos(20)\r<BR>\n" );
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document.write( "a^2 = 180 - 144*cos(20º)\r<BR>\n" );
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document.write( "Use your calculator find cos(20º). Make sure your calculator is in DEGREE MODE and not RADIAN MODE.\r<BR>\n" );
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document.write( "a^2 = 180 - 144 * (0.939692621)<BR>\n" );
document.write( "a^2 = 44.6842626<BR>\n" );
document.write( "a = 6.68462883\r<BR>\n" );
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document.write( "We know that (1/2)(a)(b) gives us the area.\r<BR>\n" );
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document.write( "We have a and we have b.\r<BR>\n" );
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document.write( "(1/2)(6.68462883)(6) = 20.053888565 cm.\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=20.1 ALIGN=MIDDLE  ALT=\"20.1\"   DISABLED_style= \"max-width:90%; height:auto;\" >cm when rounded.\r<BR>\n" );
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document.write( " </SPAN>\n" );
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