document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=443556>Question 443556</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Hi,\r<BR>\n" );
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document.write( "I have this problem on my Coure Test Review Packet. Its asking me 'What is the area of a circle with the circumference of 18pie?' But I don't understand it. Im not very good at circles so I don't know how to do it. Please help.\r<BR>\n" );
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document.write( "Justice </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #305907 by </B><A HREF=/tutors/aboutme.mpl?userid=richard1234><B>richard1234(7193)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=richard1234><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=richard1234><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=305907\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> This problem is simply applying the area/circumference formulas for circles. The circumference C is 18pi, so\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=\"/cgi-bin/rendertex.cgi?C = \LARGE 18\pi = 2\pi r\">. This implies r = 9.\r<BR>\n" );
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document.write( "Given the area formula <IMG STYLE=\"max-width:80%;\" SRC=\"/cgi-bin/rendertex.cgi?\LARGE A = \pi r^2\">, we replace r with 9 to obtain\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=\"/cgi-bin/rendertex.cgi?\LARGE A = \pi (9^2) = 81\pi\">\r<BR>\n" );
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document.write( "The circumference/area formulas are very useful to know. I usually advise knowing how to derive the formulas as well so that it does not become rote memorization. However you probably won't learn the proof of the area/circumference of a circle until you take a calculus course. </SPAN>\n" );
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