(i) Given the points \(A(2,-6), B(2,6)\) and \(C(-2,-6)\), prove that they lie on a circle \(K\) whose centre is the origin \(O(0, 0)\). What is the radius of circle \(K\)?
 
Answer:
 
The points \(A\), \(B\) and \(C\) on the circle \(K\).
 
Radius \(=\) i

(ii) Given the points \(D(2, -6)\) and \(E(0, 6)\), prove whether \(D\) and \(E\) lie within the circle, on the circle, or outside the circle \(K\).
 
Answer:
 
The point \(D\) lies the circle \(K\).
 
The point \(E\) lies the circle \(K\).