document.write( "Question 1199445: A circle passes through the points (6,3), (6,-3) and (2,5).Find the centre,radius, and equation of the circle \n" ); document.write( "
Algebra.Com's Answer #833327 by Alan3354(69443)\"\" \"About 
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A circle passes through the points A(6,3), B(6,-3) and C(2,5). Find the centre, radius, and equation of the circle
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\n" ); document.write( "Find the perpendicular bisectors of AB and AC.
\n" ); document.write( "For AB, it's the x-axis.
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\n" ); document.write( "For AC:
\n" ); document.write( "Find the midpoint:
\n" ); document.write( "x: (6+2)/2 = 4
\n" ); document.write( "y: (3+5)/2 = 4
\n" ); document.write( "(4,4) is the midpoint
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\n" ); document.write( "The slope of AC is (5-3)/(2-6) = -1/2
\n" ); document.write( "The slope of lines perpendicular to AC = 2
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\n" ); document.write( "Thru (4,4) with m = 2 ---> y-4 = 2(x-4)
\n" ); document.write( "y = 2x-4 is the equation of the perpendicular bisector to AC
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\n" ); document.write( "The intersection of y = 2x-4 and the x-axis is the center of the circle.
\n" ); document.write( "At the x-axis, y = 0
\n" ); document.write( "0 = 2x-4 ---> x = 2
\n" ); document.write( "The center is (2,0)
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\n" ); document.write( "The radius is the distance between the center and any of the 3 given points.
\n" ); document.write( "r^2 = diffy^2 + diffx^2
\n" ); document.write( "r^2 = (3-0)^2 + (6-2)^2 = 25
\n" ); document.write( "\"%28x-2%29%5E2+%2B+y%5E2+=+25\"
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