document.write( "Question 1041504: The circle passes through the points (-4,8),(4,-4), and(3,-9). \n" ); document.write( "

Algebra.Com's Answer #656461 by Alan3354(69443) $\"\"$ $\"About$

You can put this solution on YOUR website!
The circle passes through the points (-4,8),(4,-4), and(3,-9).
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\n" ); document.write( "You didn't say what you want to do.
\n" ); document.write( "If you want to find the equation of the circle:
\n" ); document.write( "Label the points A(-4,8), B(4,-4), and C(3,-9).
\n" ); document.write( "Find the perpendicular bisector of AB and of BC.
\n" ); document.write( "Find the intersection of the 2 bisectors, that's the center of the circle (h,k).
\n" ); document.write( "The distance from the center to any point is the radius.
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\n" ); document.write( " $\"%28x-h%29%5E2+%2B+%28y-k%29%5E2+=+r%5E2\"$
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\n" ); document.write( "That's one way to do it.
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\n" ); document.write( "I prefer to use a matrix.
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document.write( "| x^2+y^2    x    y   1|\r\n" );
document.write( "|x1^2+y1^2  x1   y1   1|\r\n" );
document.write( "|x2^2+y2^2  x2   y2   1|  = 0\r\n" );
document.write( "|x3^2+y3^2  x3   y3   1|\r\n" );
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