Find the coordinates of the circumcentre of the triangle whose vertices are (3, 0), (-1, -6) and (4,-1). Also, find its circumradius.

Coordinates of points on a circle are A (3, 0), B(-1, -6) and C(4,-1)


Let the coordinates of the centre of the circle be O(x, y)


Using distance formula =


Since the distance of the points A, B and C will be equal from the center, therefore


OA = OC



On squaring both sides, we get


=


x2 + 9 - 6x + y2 = x2 + 2x +1 + y2 + 36 + 12y


-8x - 12y = 28


2x + 3y = -7------------- (1)


Similarly, OC = OB



On squaring both sides, we get


=


x2 + 16 - 8x + y2 + 1 + 2y = x2 + 1 +2x + y2 + 36 + 12y


-10x - 10y = 20


x + y = -2 ------------- (2)


Solving eqn (1) and (2), we get


x = 1; y = -3


Coordinates of circum center are (1, -3)


Circum radius of the circle = OA =


=


= units


27