Prove that the points `A(4, 0), B(6, 1), C(4, 3)` and D(3, 2) are concyclic.

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

Prove that the points A(0, 4, 1), B(2, 3, -1), C(4, 5, 0) and D(2, 6, 2) are vertices of a square.

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

Prove that the points A(0,1), B(1,4), C(4,3) and D(3,0) are the vertices of a square ABCD.

Prove that the points (2,0), (-2,0),(-1,3) and (1,-1) are concyclic.

Prove that the points A(-2,-1) B(1,0), C(4,3) and D(1,2) are the vertices of a parallelogram. Is it a rectangle ?

Using slopes, prove that the points A(-2,-1) , B(1,0) , C(4,3) and D(1,2) are the vertices of a parallelogram.

Using slopes, prove that the points A(-2,-1) , B(1,0) , C(4,3) and D(1,2) are the vertices of a parallelogram.

The distinct points A(0,0),B(0,1),C(1,0), and D(2a,3a) are concyclic than

If the points (2,0),(0,1),(4,0) and (0,a) are concyclic then a=