document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=30116>Question 30116</A>: <I><SPAN STYLE=\"word-break: break-all;\"> In (triangle)ABC, if A and B are acute angles, and sin A =10/13 , <BR>\n" );
document.write( "what is the value of cos A ?\r<BR>\n" );
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document.write( "please help, need to know how to do this on my calculator too.<BR>\n" );
document.write( "thank you </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #16845 by </B><A HREF=/tutors/aboutme.mpl?userid=Paul><B>Paul(988)</B></A><img src=\"/images/stars/stars-11.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Paul><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=16845\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> In triangle AB, A and B are acute angles so. AC and BC are right angles.<BR>\n" );
document.write( "Sin A = 10/13<BR>\n" );
document.write( "13 is the hypotenuse side and 10 is the opposite side.<BR>\n" );
document.write( "To find cos A.<BR>\n" );
document.write( "From pythagorean thereom:\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=\"/cgi-bin/rendertex.cgi?a^2+b^2=c^2\">\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=\"/cgi-bin/rendertex.cgi?10^2+b^2=13^2\">\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=\"/cgi-bin/rendertex.cgi?b=\sqrt{69}\">\r<BR>\n" );
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document.write( "b=8.3\r<BR>\n" );
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document.write( "SO the value for cos A is 8.3/13<BR>\n" );
document.write( "cos A=0.63 take the inverse sine of cosine:<BR>\n" );
document.write( "cos A=51 degrees.<BR>\n" );
document.write( "PAul. </SPAN>\n" );
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