document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=392026>Question 392026</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The graph of the function x^2+y^2+20x-16y+80=0 is a circle. What are the coordinates of the center and the length of the radius?<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 #278234 by </B><A HREF=/tutors/aboutme.mpl?userid=stanbon><B>stanbon(75887)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=stanbon><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=278234\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\">  The graph of the function x^2+y^2+20x-16y+80=0 is a circle. What are the coordinates of the center and the length of the radius?\r<BR>\n" );
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document.write( "Complete the square:<BR>\n" );
document.write( "x^2+20x+100 + y^2-16y+64 = -80+100+64<BR>\n" );
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document.write( "Factor:<BR>\n" );
document.write( "(x+10)^2 + (y-8)^2 = 84<BR>\n" );
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document.write( "Center: (-10,8)<BR>\n" );
document.write( "Radius: sqrt(84) = 2sqrt(21)<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H. </SPAN>\n" );
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