document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=98840>Question 98840</A>This question is from textbook <A HREF=http://www.amazon.com/exec/obidos/ASIN/0130800066/algebrahomeworkh></A><BR>\n" );
document.write( ": <I><SPAN STYLE=\"word-break: break-all;\"> one question: about finding center and radius  (circle graph) : \r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+3x%5E2+%2B+3y%5E2+-+6x+%2B+12y=+0+ ALIGN=MIDDLE  ALT=\"+3x%5E2+%2B+3y%5E2+-+6x+%2B+12y=+0+\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "i did this:\r<BR>\n" );
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document.write( "(3x^2 -6x) + (3y^2 +12y)=0\r<BR>\n" );
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document.write( "then I complete the square:\r<BR>\n" );
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document.write( "-6/2 = -3^2=9    and   12/2 =6^2=36\r<BR>\n" );
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document.write( "then:\r<BR>\n" );
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document.write( "(3x^2-6x+9) + (3y^2+12y+36)= 9+36\r<BR>\n" );
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document.write( "(3x-3)^2 + (3y +6)^2 =45\r<BR>\n" );
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document.write( "factor:\r<BR>\n" );
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document.write( "3(x-1) + 3(y+2)= 45\r<BR>\n" );
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document.write( "i got the answer for center:\r<BR>\n" );
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document.write( "C(1,-2) \r<BR>\n" );
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document.write( "and the answer to the raduis is square root of 5\r<BR>\n" );
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document.write( "which i dont know how they got it.\r<BR>\n" );
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document.write( "thank you\r<BR>\n" );
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document.write( " </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #71902 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=71902\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Find center and radius:<BR>\n" );
document.write( "3x^2 + 3y^2 - 6x + 12y= 0<BR>\n" );
document.write( "Divide thru by 3 to get:<BR>\n" );
document.write( "x^2+y^2-2x+4y=0<BR>\n" );
document.write( "Complete the square on the x-terms and y-terms separately:\r<BR>\n" );
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document.write( "x^2-2x+1 + y^2+4y+4 = 1+4<BR>\n" );
document.write( "(x+1)^2 + (y+2)^2 = 5<BR>\n" );
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document.write( "Center at (-1,-2)<BR>\n" );
document.write( "Radius = sqrt(5)<BR>\n" );
document.write( "===============<BR>\n" );
document.write( "Cheers,<BR>\n" );
document.write( "Stan H. </SPAN>\n" );
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