document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=730924>Question 730924</A>: <I><SPAN STYLE=\"word-break: break-all;\"> What is the centre and radius of the circle with the equation x^2+y^2-2y-15=15 </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #446919 by </B><A HREF=/tutors/aboutme.mpl?userid=lwsshak3><B>lwsshak3(11628)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=lwsshak3><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=446919\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> What is the centre and radius of the circle with the equation <BR>\n" );
document.write( "x^2+y^2-2y-15=15<BR>\n" );
document.write( "Standard form of equation for a circle: (x-h)^2+(y-k)^2=r^2, (h,k)=(x,y) coordinates of center, r=radius<BR>\n" );
document.write( "For given equation:<BR>\n" );
document.write( "x^2+y^2-2y=30<BR>\n" );
document.write( "complete the square:<BR>\n" );
document.write( "x^2+(y^2-2y+1)=30+1<BR>\n" );
document.write( "x^2+(y-1)^2=31<BR>\n" );
document.write( "center: (0,1)<BR>\n" );
document.write( "radius: &#8730;31 </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );