(i) With A as centre and a suitable radius greater than ½ AB of length, draw arcs on either side of AB.
(ii) With the same radius and B as centre, cut the previous pair of arcs at points P and Q.(iii) Join PQ.
(iv) M is the point of intersection of AB and PQ.(v) PQ bisects AB at M, AM = MB.
(vi) \PQ is the perpendicular bisector of AB.