document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=757962>Question 757962</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The are of a circle is directly proportional to the square of its radius. A circle with a radius of 2cm has an are of 12.566 cm^2. What is the radius of a circle with an area of 78.54cm^2?\r<BR>\n" );
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document.write( "Round to the nearest unit. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #461249 by </B><A HREF=/tutors/aboutme.mpl?userid=Cromlix><B>Cromlix(4381)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Cromlix><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=Cromlix><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=461249\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> area is directly proportional to<BR>\n" );
document.write( "the square of its radius.<BR>\n" );
document.write( "A = kr^2<BR>\n" );
document.write( "(k is the constant of proportionality)<BR>\n" );
document.write( "12.566 = k 2^2<BR>\n" );
document.write( "   k = 12.566/4<BR>\n" );
document.write( "   k = 3.1415<BR>\n" );
document.write( "Formula: A = 3.1415 r^2<BR>\n" );
document.write( "       78.54 = 3.1415 r^2<BR>\n" );
document.write( "       78.54/3.1415 = r^2<BR>\n" );
document.write( "               r^2 = 25<BR>\n" );
document.write( "                 r = 5cm\r<BR>\n" );
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document.write( "Hope this helps.<BR>\n" );
document.write( ":-)<BR>\n" );
document.write( " </SPAN>\n" );
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