document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=337106>Question 337106</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Find the value of tan (a - b) if cos a= -3/5, sin b= 5/13, 90 < a < 180, and 90 < b < 180  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #241642 by </B><A HREF=/tutors/aboutme.mpl?userid=CharlesG2><B>CharlesG2(834)</B></A><img src=\"/images/stars/stars-11.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=CharlesG2><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=241642\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Find the value of tan (a - b) if cos a= -3/5, sin b= 5/13, 90 < a < 180, and 90 < b < 180 \r<BR>\n" );
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document.write( "cos a = -3/5 = -0.6<BR>\n" );
document.write( "a = 126.8699 degrees to 4 places\r<BR>\n" );
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document.write( "sin b = 5/13 = 0.3846 to 4 places\r<BR>\n" );
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document.write( "b = 22.6199 degrees to 4 places, but this is not between 90 and 180\r<BR>\n" );
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document.write( "sin 0 = 0, sin 45 = sqrt(2)/2 = 0.7071 to 4 places, sin 90 = 1,<BR>\n" );
document.write( "sin 135 = sqrt(2)/2, sin 180 = 0\r<BR>\n" );
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document.write( "180 - b = 157.3801 degrees to 4 places, use this for b\r<BR>\n" );
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document.write( "tan (a - b) = tan (126.8699 - 157.3801) = tan (-30.5102)<BR>\n" );
document.write( "tan (a - b) = -0.5893 to 4 places\r<BR>\n" );
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