A circle C passes through the points (-7,-2),(-1,4),and (1,2). find the center a

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A circle C passes shrough the points (-7,-2), (-1,4) and (1,2).find the center dan radius of C (-7,-2) => (x + 7)2 + (y +2)2 =r2 .... i) (-1.4) => ( x + 1)2 + (y - 4)2 =r2   ... ii) (1,2) => (x - 1)2 + (y - 2)2 =r2 ..... iii) i) - ii) : x2 + 14x + 49 + y2 + 4y + 4 =r2           x2 + 2x +    1 + y2- 8y +16 = r2 -                  12x + 12y + 36 = 0 => x + y + 3 = 0 ... iv) i) - iii) : x2 + 14x + 49 + y2 + 4y + 4 =r2            x2 - 2x + 1     + y2 -4y + 4 = r2 -                  16x + 8y + 48 = 0 => 2x + y + 6 = 0 ... v) iv) - v) : x + y + 3 = 0             2x + y + 6 = 0 -              -x - 3 = 0 => x = -3      insert x = -3 to iv) : -3 + y + 3 = 0=> y = 0 insert x = -3 and y = 0 to i) : (-3+7)2 + (0 +2)2 = r2 => r2 = 20 => r =25 center at point (-3 , 0) and radius 25

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