document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=227118>Question 227118</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Where is the center of the circle given by the equation (x + 7)2 + (y - 5)2 = 16?  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #168864 by </B><A HREF=/tutors/aboutme.mpl?userid=Theo><B>Theo(13342)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Theo><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=Theo><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=168864\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> This looks like the vertex form of the equation for a circle.\r<BR>\n" );
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document.write( "The general form of that should be:\r<BR>\n" );
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document.write( "(x-h)^2 + (y-k)^2 = r^2\r<BR>\n" );
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document.write( "where:\r<BR>\n" );
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document.write( "(h,k) is the (x,y) coordinates of the center of the circle.\r<BR>\n" );
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document.write( "Since -h = +7, then h must be -7.\r<BR>\n" );
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document.write( "Since -k = -5, then k must be 5.\r<BR>\n" );
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document.write( "Center of your circle is at x,y) = (-7,5)\r<BR>\n" );
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document.write( "To graph your circle, we need to solve for y.\r<BR>\n" );
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document.write( "Your equation is:\r<BR>\n" );
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document.write( "(x + 7)^2 + (y - 5)^2 = 16\r<BR>\n" );
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document.write( "Subtract (x+7)^2 from both sides to get:\r<BR>\n" );
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document.write( "(y-5)^2 = 16 - (x+7)^2)\r<BR>\n" );
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document.write( "Take the square root of both sides of the equation to get:\r<BR>\n" );
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document.write( "y-5 = +/- <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=sqrt%2816-%28x%2B7%29%5E2%29 ALIGN=MIDDLE  ALT=\"sqrt%2816-%28x%2B7%29%5E2%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "Add 5 to both sides of the equation to get:\r<BR>\n" );
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document.write( "y = 5 +/- <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=sqrt%2816-%28x%2B7%29%5E2%29 ALIGN=MIDDLE  ALT=\"sqrt%2816-%28x%2B7%29%5E2%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "graph of your equation looks like.....\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=graph%28600%2C600%2C-13%2C2%2C-2%2C13%2C5%2Bsqrt%2816-%28x%2B7%29%5E2%29%2C5-sqrt%2816-%28x%2B7%29%5E2%29%29 ALIGN=MIDDLE   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( " </SPAN>\n" );
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