document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1089625>Question 1089625</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Island A is 160 miles from island B. A ship captain travels 220 miles from island A and then finds that he is off course and 200 miles from island B. What bearing should he turn to, so he is heading straight towards island B? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #704006 by </B><A HREF=/tutors/aboutme.mpl?userid=ankor@dixie-net.com><B>ankor@dixie-net.com(22740)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=ankor@dixie-net.com><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=ankor@dixie-net.com><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=704006\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Island A is 160 miles from island B. A ship captain travels 220 miles from island A and then finds that he is off course and 200 miles from island B.<BR>\n" );
document.write( " What bearing should he turn to, so he is heading straight towards island B?<BR>\n" );
document.write( ": <BR>\n" );
document.write( "Draw this out as a triangle ABC where A & B are the islands and C it the point that the ship changes it's heading towards B<BR>\n" );
document.write( " Use the law of cosines; c^2 = a^2 + b^2 - 2(ab)Cos(C), where<BR>\n" );
document.write( "a = 200<BR>\n" );
document.write( "b = 220<BR>\n" );
document.write( "c = 160<BR>\n" );
document.write( "Arrange as<BR>\n" );
document.write( "2(ab)Cos(C) = a^2 + b^2 - c^2 <BR>\n" );
document.write( "2(200*220)Cos(C) = 200^2 + 220^2 - 160^2<BR>\n" );
document.write( "2(44000)Cos(C) = 40000 + 48400 - 25600<BR>\n" );
document.write( "2(44000)Cos(C) = 62800<BR>\n" );
document.write( "Simplify, divide both sides by 2<BR>\n" );
document.write( "44000*Cos(C) = 31400<BR>\n" );
document.write( "Cos(C) = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=31400%2F44000 ALIGN=MIDDLE  ALT=\"31400%2F44000\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Cos(C) = .7136<BR>\n" );
document.write( "ArcCos = 44.47 degree, therefore<BR>\n" );
document.write( "180 - 44.47 = 135.5 degree turn to head towards Island B </SPAN>\n" );
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