A chord AB of a circle whose centre is O, is bisected at E by a diameter CD. OC= OD = 15cm and OE = 9 cm. Find the length of AB
Circle
Given OE = 9 cm, OA = 15cm
Consider △OAE, ∠OEA=90o
Applying Pythagoras theorem
AE2 = OA2 − OE2
AE2 = 152 − 92
AE2 = 225 − 81 =144
⇒AE=12cm
∴AB=2 × 12 = 24cm [the perpendicular from the centre bisects the chord]