Q10 of 52 Page 154

Radius of a sector of a circle is 7 cm. If measure of arc of the sector is –

(l) 30°


(ll) 210°


(lll) three right angles


Find the area of sector in each case.

Radius of circle, r = 7cm


(l) Angle subtended by arc, θ = 30°


As we know,




⇒ Al = 12. 83 sq. cm


(ll) Angle subtended by arc, θ = 210°


Similarly,



⇒ All = 89.83 sq. cm


(lll) Angle subtended by arc, θ = (3× 90)° = 270°


Similarly,



⇒ Alll = 115.5 sq. cm


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