document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=698758>Question 698758</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A triangle has sides of length 5cm, 6cm, and 9cm.<BR>\n" );
document.write( "calculate the value of angle x.\r<BR>\n" );
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document.write( "(X is opposite the 6cm side)<BR>\n" );
document.write( "i dont know what equation to use </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #431014 by </B><A HREF=/tutors/aboutme.mpl?userid=vidya+p><B>vidya p(12)</B></A><img src=\"/images/stars/stars-06.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=vidya+p><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=431014\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Solution:<BR>\n" );
document.write( "LEt ABC is a triangle, with sides of measure, AB= c,AC = b,BC = a<BR>\n" );
document.write( "the angle opposite of side 6 cm is x, <BR>\n" );
document.write( "now to find the angle with the given three sides, <BR>\n" );
document.write( "we can make use of the cosine rule which says that, <BR>\n" );
document.write( "a^2 = b^2 + c^2 - 2bc cos (B) <BR>\n" );
document.write( "6^2 = 9^2 + 5^2 - 2(9)(5)*cos x , <BR>\n" );
document.write( "36 = 81 + 25 - 90*cos (x) <BR>\n" );
document.write( "36 - 106 = -90*cos(x) <BR>\n" );
document.write( "-70 / -90 = cos (x) <BR>\n" );
document.write( "x = arccos( 7/9) \r<BR>\n" );
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document.write( "Thanks <BR>\n" );
document.write( "Best regards. </SPAN>\n" );
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