In the given figure, OABC is a quadrant of a circle with centre O and radius 3.5 cm. If OD = 2 cm, find the area of the shaded region.
Given:
Radius of Circle = 3.5 cm
OD = 2 cm
∵ Area of Quadrant = 
πr2
∴ Area of Quadrant OABC = 
× 
× 3.5 × 3.5
= 9.625 cm2
∵ Area of Triangle = 
× Base × Height
∴ Area of 
COD = 
× 3.5 × 2
= 3.5 cm2
Area of Shaded Region = Area of Quadrant OABC – Area of 
COD
= 38.5 – 3.5 = 35 cm2
Hence, the area of shaded region is 35 cm2.
34