Q17 of 68 Page 15

Find the area of the shaded region in Fig.15.72, if AC=24cm, BC=10cm and O is the centre of the circle.

Given,


AC = 24 cm


BC = 10 cm


By Pythagoras theorem


AB2 = AC2 + BC2


= 242+102 = 576 + 100 = 676


AB = = 26cm


Radius of semi-circle with diameter AB = = 13cm


Area of semi-circle = = 265.33cm2


Area of triangle ABC = = 120cm2


So,


Area of shaded region = area of semi-circle – area of triangle


= 265.33 – 120 = 145.33 cm2


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