document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1077350>Question 1077350</A>: <I><SPAN STYLE=\"word-break: break-all;\"> I need to find the center and radius by hand and having difficulty;\r<BR>\n" );
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document.write( "x^2-10x+y^2+6y=15 </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #691828 by </B><A HREF=/tutors/aboutme.mpl?userid=math_helper><B>math_helper(2461)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=math_helper><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=math_helper><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=691828\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+x%5E2-10x%2By%5E2%2B6y=15+ ALIGN=MIDDLE  ALT=\"+x%5E2-10x%2By%5E2%2B6y=15+\"   DISABLED_style= \"max-width:90%; height:auto;\" > can be rewritten by completing the squares:<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+%28x%5E2-10x+%2B+25%29+%2B+%28y%5E2%2B6y+%2B+9%29+=+15+%2B+9+%2B+25+ ALIGN=MIDDLE  ALT=\"+%28x%5E2-10x+%2B+25%29+%2B+%28y%5E2%2B6y+%2B+9%29+=+15+%2B+9+%2B+25+\"   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%2B3%29%5E2+=+49+ ALIGN=MIDDLE  ALT=\"++%28x-5%29%5E2+%2B+%28y%2B3%29%5E2+=+49+\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "Compare this to the general form of the equation of a circle <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+%28x-x%5B0%5D%29%5E2+%2B+%28y-y%5B0%5D%29%5E2+=+r%5E2+ ALIGN=MIDDLE  ALT=\"+%28x-x%5B0%5D%29%5E2+%2B+%28y-y%5B0%5D%29%5E2+=+r%5E2+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "where (<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+x%5B0%5D+ ALIGN=MIDDLE  ALT=\"+x%5B0%5D+\"   DISABLED_style= \"max-width:90%; height:auto;\" >, <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=y%5B0%5D ALIGN=MIDDLE  ALT=\"y%5B0%5D\"   DISABLED_style= \"max-width:90%; height:auto;\" >) = coordinates of the center\r<BR>\n" );
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document.write( "and you get<BR>\n" );
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document.write( "center at ( <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+highlight%285%29+ ALIGN=MIDDLE  ALT=\"+highlight%285%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" > ,<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+highlight%28-3%29+ ALIGN=MIDDLE  ALT=\"+highlight%28-3%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" > )  and  <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=r+=+sqrt%2849%29+=+highlight%287%29%29 ALIGN=MIDDLE  ALT=\"r+=+sqrt%2849%29+=+highlight%287%29%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > </SPAN>\n" );
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