document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=397952>Question 397952</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Decide whether or not this equation has a circle as its graph. If it does, give the center and the radius.<BR>\n" );
document.write( "8x^2+40x+8y^2+24y-60=0 </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #281971 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=281971\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> 8x^2+40x+8y^2+24y-60=0\r<BR>\n" );
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document.write( "standard form for a circle<BR>\n" );
document.write( "(x-h)^2+(y-k)^2=r^2, with (h,k) being the coordinates of the center, and r=radius.<BR>\n" );
document.write( "completing squares<BR>\n" );
document.write( "8(x^2+5x+25/4)+8(y^2+3y+9/4)=60+50+18=128<BR>\n" );
document.write( "divide by 8<BR>\n" );
document.write( "(x+5/2)^2+(y+3/2)^2=16\r<BR>\n" );
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document.write( "center(-5/2,-3/2) \r<BR>\n" );
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document.write( "r^2=16<BR>\n" );
document.write( "r=4<BR>\n" );
document.write( "ans: this is a circle with center at (-5/2,-3/2), and radius=4 \r<BR>\n" );
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