document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=933905>Question 933905</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Hello. My name is Jonny. I am a fifth year pupil attending an academy located in Scotland. Currently, I am struggling with one of the questions presented in my school-issued copy of Heinemann Mathematics (second edition). The question [7] appears in exercise 11J and is worded as follows:\r<BR>\n" );
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document.write( "\"The diagram shows two telegraph poles, AB and ED, with support wires pegged at a single point C. Find the exact value of a) cos ACB; b) sin ECD; c) cos ACE; d) sin ACE\"\r<BR>\n" );
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document.write( "The diagram shows two right-angled triangles (one [ABC], and another [ECD]), facing one another, intersect at point C on a straight horizontal line. Furthermore, the left-most triangle exhibits lengths of AB [opposite] (6m) and BC [adjacent] (10m). The right-most triangle exhibits lengths ED [opposite] (5m) and CD [adjacent] (3m).\r<BR>\n" );
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document.write( "I have successfully tackled parts \"a\" and \"b\" - with both answers coming to (5/&#8730; 34). However, I cannot understand how to solve \"c\", and subsequently, \"d\".\r<BR>\n" );
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document.write( "Any assistance on answering the question would be very much appreciated. Thank you for taking the time to read and consider my enquiry. \r<BR>\n" );
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document.write( "Additional information: The question/exercise is an element of the double-angle/addition formulae section, in regards to trigonometry.  \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 #567110 by </B><A HREF=/tutors/aboutme.mpl?userid=MathLover1><B>MathLover1(20850)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=MathLover1><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=MathLover1><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=567110\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <BR>\n" );
document.write( "here is your solution:\r<BR>\n" );
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document.write( "https://www.youtube.com/watch?v=ZoANdQzZzQ8 </SPAN>\n" );
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