Q5 of 31 Page 65

If the length of a chord of a circle is 48 cm and the distance of it from the centre is 7 cm. then let us write by calculating, the length of radius of the circle.


Given AB = 48cm, OP = 7cm


AP


Perpendicular from the center of the circle to any Chord bisects it in two line segments



⇒ AP = 24cm


In OAP, Using Pythagoras Theorem


⇒ OA2 = AP2 + OP2


⇒ OA2 = 242 + 72


⇒ OA2 = 576 + 49


⇒ OA2 = 625


⇒ OA = 25cm


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