document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1133873>Question 1133873</A>: <I><SPAN STYLE=\"word-break: break-all;\"> if sin A=6÷13 and SecB=13÷6 then A+B is equal to<BR>\n" );
document.write( "150°<BR>\n" );
document.write( "90°<BR>\n" );
document.write( "60°<BR>\n" );
document.write( "45° </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #751213 by </B><A HREF=/tutors/aboutme.mpl?userid=greenestamps><B>greenestamps(13200)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=greenestamps><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=greenestamps><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=751213\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <br><BR>\n" );
document.write( "There is indeed no need to calculate anything; but the two angles are not each 45 degrees.  (sin(45) is not 6/13....)<br><BR>\n" );
document.write( "We are given sinA = 6/13 and secB = 13/6.  We then know that cosB = 6/13.<br><BR>\n" );
document.write( "So we have an angle A whose sine is the same as the cosine of another angle B.<br><BR>\n" );
document.write( "Picture a right triangle with A and B as the acute angles.  Then the basic definition of sine and cosine tells us that the sine of one of the angles is the cosine of the other.<br><BR>\n" );
document.write( "So, because we have two angles with the sine of one being equal to the cosine of the other, we know the angles are the acute angles of a right triangle; therefore their sum is 90 degrees. </SPAN>\n" );
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