document.write( "Question 83212: Find the center and radius of the circle
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Algebra.Com's Answer #60042 by jim_thompson5910(35256)\"\" \"About 
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\"3+%2A+x+%5E+2+%2B+y+%5E+2+-+6+%2A+x+%2B+4+%2A+y+-+4++++=0\" Start with the given conic\r
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\n" ); document.write( "\n" ); document.write( "\"3+%2A+x+%5E+2+%2B+y+%5E+2+-+6+%2A+x+%2B+4+%2A+y+=+4+++\"Add 4 to both sides\r
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\n" ); document.write( "\n" ); document.write( "\"%28+3+%2A+x+%5E+2+-+6+%2A+x+%29+%2B+%28+y+%5E+2+%2B+4+%2A+y+%29+=+4+++\" Group like terms\r
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\n" ); document.write( "\n" ); document.write( "\"3+%28+x+%5E+2+-+2+%2A+x+%29+%2B+1+%28+y+%5E+2+%2B+4+%2A+y+%29+=+4+\" Factor a 3 out of the first parenthesis
\n" ); document.write( "and factor a 1 out of the second parenthesis.\r
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\n" ); document.write( "\n" ); document.write( "Now we must complete the individual squares inside the parenthesis:\r
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\n" ); document.write( "\n" ); document.write( " For instance to complete \"3+%28+x+%5E+2+-+2+%2A+x+%29+\", take half of -2 and square it (ie \"%28-2%2F2%29%5E2=%28-1%29%5E2=1\" to get 1. Now add 1 inside the parenthesis like this: \r
\n" ); document.write( "\n" ); document.write( "\"3+%28+x+%5E+2+-+2+%2A+x+%2B+1+%29+\"\r
\n" ); document.write( "\n" ); document.write( "Since you really added \"3%2A1\" to the entire left side, we must add \"3%2A1\" to the right side also. Now lets complete \"1+%28+y+%5E+2+%2B+4+%2A+y+%29\"\r
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\n" ); document.write( "\n" ); document.write( "In order to complete \"1+%28+y+%5E+2+%2B+4+%2A+y+%29\", take half of 4 and square it (ie \"%284%2F2%29%5E2=%282%29%5E2=4\" to get 4. Now add 4 inside the parenthesis like this: \r
\n" ); document.write( "\n" ); document.write( "\"1+%28+y+%5E+2+%2B+4+%2A+y+%2B+4+%29\"\r
\n" ); document.write( "\n" ); document.write( "Since you really added \"1%2A4\" to the entire left side, we must add \"1%2A4\" to the right side also.\r
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\n" ); document.write( "\n" ); document.write( " Complete the individual squares by taking half of the 2nd coefficient and squaring it (remember to add to both sides).\r
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\n" ); document.write( "\n" ); document.write( "\"3+%28+x+%5E+2+-+2+%2A+x+%2B+1+%29+%2B+1+%28+y+%5E+2+%2B+4+%2A+y+%2B+4+%29+=+1+1+\" Combine like terms on the right side\r
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\n" ); document.write( "\n" ); document.write( "\"3+%28+x+-+1+%29+%5E+2+%2B+1+%28+y+%2B+2+%29+%5E+2+=+1+1+\" Factor the individual groups on the left side\r
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\n" ); document.write( "\n" ); document.write( "\"%28+3+%28+x+-+1+%29+%5E+2+%2B+1+%28+y+%2B+2+%29+%5E+2+%29+%2F+1+1+=+1+1+%2F+1+1+\" Divide both sides by 11\r
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\n" ); document.write( "\n" ); document.write( "\"3+%28+x+-+1+%29+%5E+2+%2F+1+1+%2B+1+%28+y+%2B+2+%29+%5E+2+%2F+1+1+=+1+\" Break up the fraction into standard form \"%28x-h%29%5E2%2Fa%5E2%2B%28y-k%29%5E2%2Fb%5E2=1\"\r
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\n" ); document.write( "\n" ); document.write( "So the equation is an ellipse where the center is (1,-2) \r
\n" ); document.write( "\n" ); document.write( "Here's the graph\r
\n" ); document.write( "\n" ); document.write( " graph of \"3+%28+x+-+1+%29+%5E+2+%2F+1+1+%2B+1+%28+y+%2B+2+%29+%5E+2+%2F+1+1+=+1+\" with the center (1,-2)
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