document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=45671>Question 45671</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Find the center and radius of the circle given by x^2+y^2-4x+8y=4 </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #30357 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=30357\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> x^2+y^2-4x+8y=4\r<BR>\n" );
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document.write( "Rearrange and complete the square on the x and the y terms, as follows:\r<BR>\n" );
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document.write( "x^2-4x+4 + y^2+8x+16 = 4 + 4 + 16<BR>\n" );
document.write( "Factor as follows:\r<BR>\n" );
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document.write( "(x-2)^2 + (y+4)^2 = 24\r<BR>\n" );
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document.write( "Center is at (2,-4)<BR>\n" );
document.write( "radius is sqrt24 = 2sqrt6\r<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H. </SPAN>\n" );
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