Question

A chord of length 8cm is drawn inside a circle of radius 6cm. Find the perpendicular distance of the chord from the centre of the circle.

Answer 1

AC = CB = 4cm

(Perpendicular from centre to a chord bisects the chord) 

In right Δ  ABO, 

By Pythagoras theorem, OA² = OC² + AC² 

OC² - 6² + 4² 

OC = 36 - 16 = 20 

OC² = `2 sqrt 5` cm

Perpendicular distance of chord from centre is `2 sqrt 5` cm