document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=82851>Question 82851</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A circle is defined by the following equation:\r<BR>\n" );
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document.write( "         2x^2+2y^2+28x+80=0\r<BR>\n" );
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document.write( "What is the radius? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #59439 by </B><A HREF=/tutors/aboutme.mpl?userid=funmath><B>funmath(2933)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=funmath><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=59439\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> A circle is defined by the following equation:\r<BR>\n" );
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document.write( "         2x^2+2y^2+28x+80=0\r<BR>\n" );
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document.write( "What is the radius?<BR>\n" );
document.write( "The standard form of the equation of a circle is: <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=highlight%28%28x-h%29%5E2%2B%28y-k%29%5E2=r%5E2%29 ALIGN=MIDDLE  ALT=\"highlight%28%28x-h%29%5E2%2B%28y-k%29%5E2=r%5E2%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >, where the center is (h,k) and the radius is r.<BR>\n" );
document.write( "First divide everything by 2 because x^2 and y^2 have to have 1 as their coefficients.<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=2x%5E2%2F2%2B2y%5E2%2F2%2B28x%2F2%2B80%2F2=0%2F2 ALIGN=MIDDLE  ALT=\"2x%5E2%2F2%2B2y%5E2%2F2%2B28x%2F2%2B80%2F2=0%2F2\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x%5E2%2By%5E2%2B14x%2B40=0 ALIGN=MIDDLE  ALT=\"x%5E2%2By%5E2%2B14x%2B40=0\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Now get the x's next to each other the y's next to each other and the constants on the other side of the = sign:<BR>\n" );
document.write( "x^2+14x+y^2+40-40=0-40<BR>\n" );
document.write( "x^2+14x+y^2=-40<BR>\n" );
document.write( "Now complete the square for the x terms.  Add 1/2 the coefficient of x squared to both sides of the =sign.<BR>\n" );
document.write( "x^2+14x+(14/2)^2+y^2=-40+(14/2)^2<BR>\n" );
document.write( "x^2+14x+(7)^2+y^2=-40+(7)^2<BR>\n" );
document.write( "x^2+14x+49+y^2=-40+49<BR>\n" );
document.write( "(x^2+14x+49)+y^2=9<BR>\n" );
document.write( "(x+7)^2+(y-0)^2=3^2<BR>\n" );
document.write( "The radius is 3.<BR>\n" );
document.write( "You didn't ask for the center, but it's (-7,0)<BR>\n" );
document.write( "Happy Calculating!!!!  </SPAN>\n" );
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