Draw a circle of radius 4 cm. Draw any two of its chords. Construct the perpendicular bisectors of these chords. Where do they meet?

Step I: Draw a circle with centre of O and a radius of 4 cm.

Step II: Draw any two chords $\overline{AB}$ and $\overline{CD}$ of the circle.
Step III: By taking A and B as centres and radii more than half of $\overline{AB}$, draw arcs on both sides of AB. The arcs intersect each other and form a perpendicular bisector $l$.
Step IV: Again take C and D as centres and radii more than half of $\overline{CD}$, draw arcs on both sides of CD. The arcs intersect each other and form a perpendicular bisector $m$.

On producing the two perpendicular bisectors meet each other at the centre O of the circle.