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( "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( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #71903 by </B><A HREF=/tutors/aboutme.mpl?userid=scott8148><B>scott8148(6628)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=scott8148><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=scott8148><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=71903\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> the first step in completing the square should be to make the coefficient of the squared term 1\r<BR>\n" );
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document.write( "in this case, the first step is to factor (reduce) if possible ... dividing by 3 gives x^2+y^2-2x+4y=0\r<BR>\n" );
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document.write( "completing the square gives x^2-2x+1+y^2+4y+4=5 ... (x-1)^2+(y+2)^2=5\r<BR>\n" );
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document.write( "if you FOIL (3x-3)^2, you don't get 3x^2-6x+9 ... similarly with (3y+6)^2 </SPAN>\n" );
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