<P> In elementary plane geometry, the power of a point is a real number h that reflects the relative distance of a given point from a given circle . Specifically, the power of a point P with respect to a circle O of radius r is defined by (Figure 1) </P> <Dl> <Dd> h = s 2 − r 2, (\ displaystyle h = s ^ (2) - r ^ (2),) </Dd> </Dl>

Power of a point with respect to a circle