document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=854810>Question 854810</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A sector of a circle has an angle at the centre of pi/4 and a perimeter of 12. Work out the radius of the circle. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #514939 by </B><A HREF=/tutors/aboutme.mpl?userid=josgarithmetic><B>josgarithmetic(39616)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=josgarithmetic><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=514939\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> r is the unknown radius.\r<BR>\n" );
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document.write( "The circumference (of the circle) would be 2*pi*r, and the arc length portion of the sector is <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%28%28pi%2F4%29%2F%282%2Api%29%29%2A%282%2Api%2Ar%29 ALIGN=MIDDLE  ALT=\"%28%28pi%2F4%29%2F%282%2Api%29%29%2A%282%2Api%2Ar%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >; which we should simplify NOW:\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=ArcPortion=%28pi%2Ar%29%2F4 ALIGN=MIDDLE  ALT=\"ArcPortion=%28pi%2Ar%29%2F4\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "The perimeter of the sector is the sum of two of r and the ArcPortion:<BR>\n" );
document.write( "Given that the perimeter is 12,<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=highlight%282r%2B%28pi%2Ar%29%2F4=12%29 ALIGN=MIDDLE  ALT=\"highlight%282r%2B%28pi%2Ar%29%2F4=12%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "This is now a fairly simple equation easily solvable for r. </SPAN>\n" );
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