document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=6644>Question 6644</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Dear Sir/Madam, \r<BR>\n" );
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document.write( "I am confronted with the following problem: \r<BR>\n" );
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document.write( "\"Find the center and radius of the circle with the following equation:<BR>\n" );
document.write( "x^2 + y^2 - 10x + 8y -40 = 0\" \r<BR>\n" );
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document.write( "I have absolutely no idea how to approach this question. I want to use the x^2 + y^2 = r^2 formula, but I don't how to integrate that into this problem. Can you please help me?\r<BR>\n" );
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document.write( "Thanks in advance.<BR>\n" );
document.write( "Regards,<BR>\n" );
document.write( "-Mike </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #3631 by </B><A HREF=/tutors/aboutme.mpl?userid=rapaljer><B>rapaljer(4671)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=rapaljer><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=rapaljer><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=3631\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> This is a completing the square problem:\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x%5E2+%2B+y%5E2+-+10x+%2B+8y+-40+=+0 ALIGN=MIDDLE  ALT=\"x%5E2+%2B+y%5E2+-+10x+%2B+8y+-40+=+0\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "Get the x terms together, and the y terms together, and leave a space after each to complete the square.  Also add + 40 to each side of the equation:\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x%5E2+-+10x+%2B+____+%2B+y%5E2+%2B+8y+%2B+____+=+40+%2B+____+%2B+____+ ALIGN=MIDDLE  ALT=\"x%5E2+-+10x+%2B+____+%2B+y%5E2+%2B+8y+%2B+____+=+40+%2B+____+%2B+____+\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "For the first blank, take half of the 10, which is 5 and square to get 25.<BR>\n" );
document.write( "For the second blank, take half of the 8, which is 4 and square to get 16.  Add these to both sides of the equation:<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x%5E2+-+10x+%2B+25+%2B+y%5E2+%2B+8y+%2B+16+=+40+%2B+25+%2B+16+ ALIGN=MIDDLE  ALT=\"x%5E2+-+10x+%2B+25+%2B+y%5E2+%2B+8y+%2B+16+=+40+%2B+25+%2B+16+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+%28x-5%29%5E2+%2B+%28y%2B4%29%5E2+=+81 ALIGN=MIDDLE  ALT=\"+%28x-5%29%5E2+%2B+%28y%2B4%29%5E2+=+81\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "Therefore this is a circle whose center is at (5, -4) and <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=r%5E2+=+81 ALIGN=MIDDLE  ALT=\"r%5E2+=+81\"   DISABLED_style= \"max-width:90%; height:auto;\" > so <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=r=9 ALIGN=MIDDLE  ALT=\"r=9\"   DISABLED_style= \"max-width:90%; height:auto;\" >. \r<BR>\n" );
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document.write( "R^2 at SCC\r<BR>\n" );
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document.write( " </SPAN>\n" );
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