Question

 In Fig. 12.30, OACB is a quadrant of a circle with centre O and radius 3.5 cm. If OD = 2 cm, find the area of the​

Answer 1

$\huge \underline \mathbb {SOLUTION:-}$

Radius of the quadrant = 3.5 cm = 7/2 cm

(i) Area of quadrant OACB = (πR²)/4 cm²

= (22/7 × 7/2 × 7/2)/4 cm²

= 77/8 cm²

(ii) Area of triangle BOD = 1/2 × 7/2 × 2 cm²

= 7/2 cm²

• Area of shaded region = Area of quadrant - Area of triangle BOD

= (77/8 - 7/2) cm2 = 49/8 cm²

= 6.125 cm²

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