Show that the points (9, 1), (7, 9), (-2, 12), (6, 10) are concyclic and find the equation of the circle on which they lie.

Show that the points (2, 0), (5, -3), (2, -6) and (-1, -3) are concyclic, find the equation of the circle on which the points lie and the coordinates of the centre of the circle.

Show that the points ( 1,0),(2,-7) , (8,1) and (9,-6) are concyclic.

Show that the four points (1, 0), (2,-7), (8, 1) and (9,- 6) are concyclic.

Prove that the points (1,- 6), (5, 2), (7, 0) and (- 1,-4) are concyclic. Find the radius of the circle.

Show that the four points (1,0), (2,-7), (8,1) and (9,-6) are concyclic.

Show that the points A(2,3,4),B(-1,2,-3) and C(-4,1,-10) are collinear. Find the equations of the line in which they lie.

Show that the points (7,5),(6,-2),(-1,-1) and (0,6) are concyclic.Also find theradius and the centre of the circle on which they lie.

Show that the following four points in each of the following are concylic and find the equation of the circle on which they lie (9,1 ) ,(7,9 ),( -2,12),(6,10)

Prove that the points (1,-6), (5,2) , (7,0) and (-1,-4) are concyclic. Find the radius of the circle .