document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=546343>Question 546343</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A triangular lot has sides of 200 meters, 180 meters, and 120 meters. Find the measure of the largest angle.        I tried solving this problem by using the Law of Cosine-    a^2=b^2+c^2-2(b)(c)cosA :     200^2=180^2+120^2-2(180)(120)cosA:           40,000=32,400+14,400-43,200cosA:     40,000=46,800-43,200cosA:       40,000-46,800=-43,200cosA:     -6800=-43,200cosA:      -6800/-43,200=cosA:          17/108=cosA    That's all I could do. I don' know how to find the cosine of a letter. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #355939 by </B><A HREF=/tutors/aboutme.mpl?userid=stanbon><B>stanbon(75887)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=stanbon><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=355939\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> A triangular lot has sides of 200 meters, 180 meters, and 120 meters. <BR>\n" );
document.write( "Find the measure of the largest angle. I tried solving this problem by using the Law of Cosine- <BR>\n" );
document.write( "a^2=b^2+c^2-2(b)(c)cosA : <BR>\n" );
document.write( "200^2=180^2+120^2-2(180)(120)cosA: <BR>\n" );
document.write( "40,000=32,400+14,400-43,200cosA: <BR>\n" );
document.write( "40,000=46,800-43,200cosA: <BR>\n" );
document.write( "40,000-46,800=-43,200cosA: <BR>\n" );
document.write( "-6800=-43,200cosA: <BR>\n" );
document.write( "-6800/-43,200=cosA: <BR>\n" );
document.write( "17/108=cosA <BR>\n" );
document.write( "---<BR>\n" );
document.write( "A = cos^-1(17/108) = 80.94 degrees<BR>\n" );
document.write( "=======================================<BR>\n" );
document.write( "Note: cos(A) = (b^2+c^2-a^2)/(2bc)<BR>\n" );
document.write( "---<BR>\n" );
document.write( "cos(A) = (180^2+120^2-200^2)/(2*180*120) = 0.1574<BR>\n" );
document.write( "---<BR>\n" );
document.write( "A = cos^-1(0.1574) = 80.94 degrees<BR>\n" );
document.write( "==========================================<BR>\n" );
document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
document.write( "----- </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );