document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1162456>Question 1162456</A>: <I><SPAN STYLE=\"word-break: break-all;\"> 20 ft. is diameter of a circular pond.  Determine side of a square pond with equal area.\r<BR>\n" );
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document.write( "Area of circle = pi * r^2\r<BR>\n" );
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document.write( "Area of square = s^2\r<BR>\n" );
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document.write( "3.1416 * 10 = 31.416 sq. ft.\r<BR>\n" );
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document.write( "Not sure how to continue.\r<BR>\n" );
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document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #786265 by </B><A HREF=/tutors/aboutme.mpl?userid=jim_thompson5910><B>jim_thompson5910(35256)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=jim_thompson5910><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=786265\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <font color=black size=3><BR>\n" );
document.write( "20 ft is the diameter<BR>\n" );
document.write( "10 ft is the radius (half the diameter)<BR>\n" );
document.write( "r = 10\r<BR>\n" );
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document.write( "Area of circle<BR>\n" );
document.write( "A = pi*r^2<BR>\n" );
document.write( "A = pi*10^2<BR>\n" );
document.write( "A = pi*10*10<BR>\n" );
document.write( "A = pi*100<BR>\n" );
document.write( "A = 100pi  ... exact area in terms of pi<BR>\n" );
document.write( "A = 100*3.14 <BR>\n" );
document.write( "A = 314 .... approximate area of the circular pond\r<BR>\n" );
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document.write( "Set this equal to s^2 and solve for s<BR>\n" );
document.write( "s^2 = 314<BR>\n" );
document.write( "s = sqrt(314)<BR>\n" );
document.write( "s = 17.7200451466693<BR>\n" );
document.write( "The square pond would have a side length of roughtly 17.72 feet if we wanted the same area as the circular pond.\r<BR>\n" );
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document.write( "Keep in mind that pi = 3.14 is an approximation, and technically not a very good one at that. To get more accuracy, you would use more decimal digits in pi\r<BR>\n" );
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document.write( "If you were to use say <BR>\n" );
document.write( "pi = 3.1415926535898<BR>\n" );
document.write( "then,<BR>\n" );
document.write( "A = 100pi<BR>\n" );
document.write( "A = 100*3.1415926535898<BR>\n" );
document.write( "A = 314.15926535898<BR>\n" );
document.write( "is the area of the circular pond<BR>\n" );
document.write( "and,<BR>\n" );
document.write( "s^2 = 314.15926535898<BR>\n" );
document.write( "s = sqrt(314.15926535898)<BR>\n" );
document.write( "s = 17.7245385090551<BR>\n" );
document.write( "So we still get 17.72 roughly, though the digits afterward are different from before. It all depends on the level of accuracy you require.\r<BR>\n" );
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document.write( "Many textbooks and teachers though use pi = 3.14 just to keep things fairly simple. So it might be best to ask the teacher which they prefer.\r<BR>\n" );
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