document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=888779>Question 888779</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A parallelogram has sides of 20cm and 30cm with an angle of 80° between the two sides. What is the length of each of the diagonals? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #537678 by </B><A HREF=/tutors/aboutme.mpl?userid=lwsshak3><B>lwsshak3(11628)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=lwsshak3><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=537678\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> A parallelogram has sides of 20cm and 30cm with an angle of 80° between the two sides. What is the length of each of the diagonals?<BR>\n" );
document.write( "***<BR>\n" );
document.write( "use law of cosines: c^2=a^2+b^2-2abcosx<BR>\n" );
document.write( "sum of angles in a parallelogram=360&#730;<BR>\n" );
document.write( "For given problem:<BR>\n" );
document.write( "a=20, b=30, x=100&#730;, c=diagonal<BR>\n" );
document.write( "c^2=20^2+30^2-2*20*30cos100&#730;<BR>\n" );
document.write( "=400+900-1200*cos100&#730;<BR>\n" );
document.write( "=1300-(-208.38)=1508.38<BR>\n" );
document.write( "c=&#8730;1508.38&#8776;38.84<BR>\n" );
document.write( "length of each of the diagonals=38.84 cm </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );