Answer 1

In right triangle ABC

AC² = AB + BC² 

= 8² + 6²

= 64 + 36

= 100

∴ AC² = 100

⇒  AC = 10 cm

Area of the shaded region = Area of circle − Area of rectangle OABC

`=> pi("OA")^2 -"AB"xx"BC"`

`⇒ 22/7xx(5)^2-8xx6`

= 78.57 - 48

= 30.57 cm² 

Hence, the area of the shaded region is 30.57 cm².