document.write( "Question 141508: circle with equation: X^2 + Y^2 - 6X - 18Y + 45
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Algebra.Com's Answer #103115 by Edwin McCravy(20086) $\"\"$ $\"About$

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circle with equation: $\"X%5E2+%2B+Y%5E2+-+6X+-+18Y+%2B+45=0\"$
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document.write( "Just solve the system\r\n" );
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document.write( "by substitution\r\n" );
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document.write( "Substitute 2Y for X in the first:\r\n" );
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document.write( "Divide every term by 5\r\n" );
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document.write( "Factor:\r\n" );
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document.write( "(Y-3)(Y-3)=0\r\n" );
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document.write( " gives \r\n" );
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document.write( "[The fact that we get only one solution tells us\r\n" );
document.write( "that the line touches the circle in only one\r\n" );
document.write( "point. So this proves that it is indeed tangent]\r\n" );
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document.write( "Now to find \r\n" );
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document.write( "Substitute  for  in\r\n" );
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document.write( "6=X\r\n" );
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document.write( "So the point of tangency is (6,3)\r\n" );
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document.write( "Edwin

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