document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=798878>Question 798878</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Did the centre and radius of the following circle: <BR>\n" );
document.write( "x^2 + y^2 = 2*r*x\r<BR>\n" );
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document.write( "Please help me!\r<BR>\n" );
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document.write( "I know the equation is (x-a)^2 + (y-b)^2 = r^2 <BR>\n" );
document.write( "Where the letters a, b and r represent numbers<BR>\n" );
document.write( "I also understand how to do this question if it was set out like this:<BR>\n" );
document.write( "x^2 + y^2 - 8*x - 9 = 0 and questions like that but I don't know how to do it if<BR>\n" );
document.write( "It is set out like the question I asked do I move r and x over or something!?\r<BR>\n" );
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document.write( "Please help me!<BR>\n" );
document.write( "Thanks!  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #482390 by </B><A HREF=/tutors/aboutme.mpl?userid=Alan3354><B>Alan3354(69443)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Alan3354><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=Alan3354><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=482390\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Did the centre and radius of the following circle: <BR>\n" );
document.write( "x^2 + y^2 = 2*r*x<BR>\n" );
document.write( "---------<BR>\n" );
document.write( "Did it what?<BR>\n" );
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document.write( "x^2 - 2rx + y^2 = 0<BR>\n" );
document.write( "x^2 - 2rx + r^2 + y^2 = r^2<BR>\n" );
document.write( "(x-r)^2 + y^2 = r^2<BR>\n" );
document.write( "The center is (r,0)<BR>\n" );
document.write( "radius = r<BR>\n" );
document.write( "------------<BR>\n" );
document.write( "For any value of r, the center is on the x-axis and the circle tangent to the y-axis. </SPAN>\n" );
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