Question

Find the diameter of the circle if the length of a chord is 3.2 cm and itd distance from the centre is 1.2 cm.

Answer 1

AD = DB = 1.6 cm (Perpendicular from centre to a chord bisects the chord)

In right Δ ODA ,

By Pythagoras theorem , OA² = OD² + AD²

= 1.6² + 1.2²

= 2.56 + 1.44

OA² = 4

OA = 2 cm

Diameter (AP) = 2 (OA) = 2 (1) = 4 cm