document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=81320>Question 81320</A>This question is from textbook <A HREF=http://www.amazon.com/exec/obidos/ASIN/0131430920/algebrahomeworkh>College Algebra</A><BR>\n" );
document.write( ": <I><SPAN STYLE=\"word-break: break-all;\"> Greetings Tutors!  Please help.\r<BR>\n" );
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document.write( "I've been going around and around on this problem:\r<BR>\n" );
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document.write( "Find an equation of the line containing the centers of the two circles\r<BR>\n" );
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document.write( "x^2 + y^2 - 4x + 6y + 4 = 0\r<BR>\n" );
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document.write( "and\r<BR>\n" );
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document.write( "x^2 + y^2 + 6x + 4y + 9 = 0\r<BR>\n" );
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document.write( "I'm not even sure where to begin.  Thanks in advance. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #58265 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=58265\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Find an equation of the line containing the centers of the two circles <BR>\n" );
document.write( "x^2 + y^2 - 4x + 6y + 4 = 0 <BR>\n" );
document.write( "complete the square to find the center:<BR>\n" );
document.write( "x^2-4x+4 +y^2+6y+9 = 9<BR>\n" );
document.write( "(x-2)^2 + (y+3)^2 = 3^2<BR>\n" );
document.write( "Center at (2,-3)<BR>\n" );
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document.write( "and <BR>\n" );
document.write( "x^2 + y^2 + 6x + 4y + 9 = 0 <BR>\n" );
document.write( "Complete the square to find the center:<BR>\n" );
document.write( "x^2+6x+9 + y^2+4y+4 = 4<BR>\n" );
document.write( "(x+3)^2 + (y+2)^2 = 262<BR>\n" );
document.write( "Center at (-3,-2)<BR>\n" );
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document.write( "Find the equation of the line thru (2,-3) and (-3,-2)<BR>\n" );
document.write( "slope = [-2--3]/[-3-2]= 1/-5 = -1/5<BR>\n" );
document.write( "Form is y=mx+b where y=-3 when x=2 and where m=-1/5<BR>\n" );
document.write( "-3=(-1/5)*2 + b<BR>\n" );
document.write( "b= -3+2/5<BR>\n" );
document.write( "b=-13/5<BR>\n" );
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document.write( "EQUATION you want: y=(-1/5)x-(13/5)<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
document.write( " </SPAN>\n" );
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