AB is a chord of a circle. The length of AB is 24 cm. P is the midpoint of AB. Perpendiculars from P on either side of the chord meets the circle at M and N respectively. If PM < PN and PM = 8 cm. then what will be the length of PN?
Answer
P is midpoint of AB. So, AP = PB = AB/2 = 24/2 = 12
If two chords of a circle intersect at a point, then
AP × PB = PM × PN
12 × 12 = 8 x PN
PN = 18
The correct option is B.