Question

Find the length of the chord of a circle in the following when: 

Radius is 1. 7cm and the distance from the centre is 1.5 cm 

Answer 1

AC = CB ----(1)  (Perpendicular from centre to a chord bisects the chord) 

In right Δ ACO, 

By Pythagoras theorem, OA² = OC² + AC² 

AC² = (1. 7)² - (1.5)² = 2.89 - 2.25 =.64 

AC = 0.8 cm 

∴ length of chord AB = 2AC     (from ( 1)) 

= 2(0.8) = 1.6 cm