Q20 of 805 Page 1

Find the area of shaded region in Fig. 4, if ABCD is a rectangle with sides 8 cm and 6 cm and O is the centre of circle. (Take π = 3.14)


In ∆ ADC

AC2 = AD2 + DC2


AC2 = 62 + 82


AC = 10 cm


Radius of circle = AC/2 = 5 cm


Area of shaded region = area of circle – area of rectangle


= π(AO)2 - AD×DC


= 3.14×25 - 6×8


= 30.5 cm2


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