Circles Part 1

For the four circles M,N,O and P, following four equations are given Circle M:x2+y2=1 Circle N:x2+y2−2x=0 Circle 0:x2+y2−2x−2y+1=0 Circle P:x2+y2−2y=0 If the centre of circle M is joined with centre of the circle N, further centre of circle N is joined with centre of the circle O, centre of circle O is joined with the centre of circle P and lastly, centre of circle P is joined with centre of circle M, then these lines form the sides of a