document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=630164>Question 630164</A>: <I><SPAN STYLE=\"word-break: break-all;\"> 	 <BR>\n" );
document.write( "Geometry. The perimeter of a semicircle is doubled when the radius is increased by 6. Find the radius of the semicircle.<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 #396758 by </B><A HREF=/tutors/aboutme.mpl?userid=dfrazzetto><B>dfrazzetto(283)</B></A><img src=\"/images/stars/stars-09.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=dfrazzetto><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=dfrazzetto><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=396758\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Assuming a closed semicircle:\r<BR>\n" );
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document.write( "P = 2r + PI*r\r<BR>\n" );
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document.write( "2P = 2(r+6) + Pi(r+6)\r<BR>\n" );
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document.write( "2P = 2r + 12 + Pi*r + 6Pi\r<BR>\n" );
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document.write( "-2P = -4r - 2Pi*r\r<BR>\n" );
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document.write( "0 = -2r - Pi*r + 12 + 6Pi\r<BR>\n" );
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document.write( "2r + Pi*r = 12 + 6Pi\r<BR>\n" );
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document.write( "r(2+Pi) = 12 + 6Pi\r<BR>\n" );
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document.write( "r(2+Pi) = 6(2+Pi)\r<BR>\n" );
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document.write( "r = 6\r<BR>\n" );
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document.write( "Check\r<BR>\n" );
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document.write( "P = 12 + 6Pi\r<BR>\n" );
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document.write( "P(r+6) = 2(12) + Pi(12)\r<BR>\n" );
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document.write( "P = 24 + 12Pi = 2 (12 + 6Pi) </SPAN>\n" );
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