document.write( "Question 1199444: A circle cuts the x-axis at (-2,0) and (4,0).It also cuts the y-axis at (0,2) and (0,-4). Determine the coordinates at the centre, radius and equation of the circle \n" ); document.write( "

Algebra.Com's Answer #833329 by htmentor(1343) $\"\"$ $\"About$

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The x coordinate of the center must lie on the midpoint of the segment from
\n" ); document.write( "(-2,0) to (4,0). This is because the perpendicular bisector of any chord
\n" ); document.write( "of a circle goes through the center. Similarly, the y coordinate of the center
\n" ); document.write( "lies on the midpoint between (0,2) and (0,-4). Thus the center of the circle is
\n" ); document.write( "(1,-1). The radius is the distance from the center to any point.
\n" ); document.write( "Thus r = sqrt((0-1)^2 + (2--1)^2) = sqrt(10)
\n" ); document.write( "So the equation is (x-1)^2 + (y+1)^2 = 10 \n" ); document.write( "

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