document.write( "Question 1121380: Find the center and radius of the following circle:
\n" ); document.write( "x2 + y2 - 12x + 8y - 29 = 0
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Algebra.Com's Answer #737248 by MathLover1(20850)\"\" \"About 
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to find the center and radius of the following circle, write given equation in this form:\r
\n" ); document.write( "\n" ); document.write( "\"%28x-h%29%5E2%2B%28y-k%29%5E2=r%5E2\" where \"h\" and \"k\" are \"x\" and \"y\" coordinates of the center, and \"r\" is the radius\r
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\n" ); document.write( "\n" ); document.write( "\"x%5E2+%2B+y%5E2+-+12x+%2B+8y+-+29+=+0+\" ......rearrange and group\r
\n" ); document.write( "\n" ); document.write( "\"%28x%5E2++-+12x%29+%2B+%28y%5E2%2B+8y+%29+=+29+\".... complete squares\r
\n" ); document.write( "\n" ); document.write( "\"%28x%5E2++-+12x%2Bb%5E2%29-b%5E2+%2B+%28y%5E2%2B+8y%2Bb%5E2+%29+-b%5E2=+29+\"\r
\n" ); document.write( "\n" ); document.write( "recall the rule: \"%28a%2Bb%29%5E2=a%5E2%2B2ab%2Bb%5E2\"\r
\n" ); document.write( "\n" ); document.write( "since you have \"2ab=12\" and \"a=1\", =>\"b=6\" for \"x\" part\r
\n" ); document.write( "\n" ); document.write( "and \"2ab=8\" and \"a=1\", =>\"b=4\" for \"y\" part\r
\n" ); document.write( "\n" ); document.write( "than you have:\r
\n" ); document.write( "\n" ); document.write( "\"%28x++-+6%29%5E2-6%5E2+%2B+%28y%2B+4%29%5E2++-4%5E2=+29+\"\r
\n" ); document.write( "\n" ); document.write( "\"%28x++-+6%29%5E2-36+%2B+%28y%2B+4%29%5E2++-16=+29+\"\r
\n" ); document.write( "\n" ); document.write( "\"%28x++-+6%29%5E2%2B+%28y%2B+4%29%5E2++-52=+29+\"\r
\n" ); document.write( "\n" ); document.write( "\"%28x++-+6%29%5E2%2B+%28y%2B+4%29%5E2++=+29%2B52+\"\r
\n" ); document.write( "\n" ); document.write( "\"%28x++-+6%29%5E2%2B+%28y%2B+4%29%5E2++=+81+\"\r
\n" ); document.write( "\n" ); document.write( "\"%28x++-+6%29%5E2%2B+%28y%2B+4%29%5E2++=+9%5E2+\"\r
\n" ); document.write( "\n" ); document.write( "now you see that: \r
\n" ); document.write( "\n" ); document.write( "\"h=6\" and \"k=-4\" and the center is at (\"6\", \"-4\")\r
\n" ); document.write( "\n" ); document.write( "and the radius is \"9\" \r
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