Find the area of the shaded region in Fig. 12.19, if PQ = 24 cm, PR = 7 cm and O is the centre of the circle.

Here, OR is the hypotenuse of as lines from two ends of diameter always make a right angle when they meet at the circumference of that circle.

Hence,


OR2 = PQ2 + PR2


OR2 = 242 + 72


OR2 = 576 + 49


OR = 25 cm


Or, radius = 12.5cm


Area of triangle = 1/2 * base *height


= 1/2 * 24 *7


Area of semicircle = 2


= 2


= 245.3125 sq cm


Hence,


Area of shaded region = 245.3125 – 84


= 161.3125 sq cm


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