SOLUTION: standard points of a circle using the point s (-6,3) (-4,-1)(-2,5) center? radius?

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Question 388559: standard points of a circle using the point s (-6,3) (-4,-1)(-2,5)
center?
radius?

Answer by robertb(5830) About Me  (Show Source):
You can put this solution on YOUR website!
The midpoint of (-6, 3) and (-4,-1) is (-5, 1). The slope of the line passing through (-6, 3) and (-4,-1) is (3--1)/(-6--4) = 4/-2 = -2. The equation of the line passing through the midpoint and perpendicular to the line through (-6, 3) and (-4,-1) is y-1 = (x--5)/2, or y+=+%28x%2B5%29%2F2+%2B+1.
The midpoint of (-2,5) and (-4,-1) is (-3, 2). The slope of the line passing through (-2, 5) and (-4,-1) is (5--1)/(-2--4) = 6/2 = 3. The equation of the line passing through the midpoint and perpendicular to the line through (-2, 5) and (-4,-1) is y-2 = -(x--3)/3, or y+=+-%28x%2B3%29%2F3+%2B+2.
The intersection of the two perpendicular bisectors is the center of the circle.
%28x%2B5%29%2F2+%2B+1%7D+=+-%28x%2B3%29%2F3+%2B+2. Multiplying both sides by 6, we get 3x%2B15+%2B+6+=+-2x-6%2B12, or 3x+21 = -2x + 6, or 5x = -15, or x = -3. To solve for y substitute into any one of the equations for the perpendicular bisector. The radius is obtained by getting the distance of the center from any one of the given points.