Q21 of 35 Page 311

The area of circumscribing circular region of an equilateral triangle is 462 sq. cm. Let us write by calculating length of each side of this triangle.


Given: Area of the circumscribing circular region = 462 cm2


Circle is centered at A.


∵ Area of a circle = πr2



⇒ r = 7√3


So, the radius of the circum circle of this triangle = 7√3 cm.


The centroid of equilateral triangle is at A and lies on height BE.



⇒ BE = 10.5√3 cm


Height of equilateral triangle = 10.5√3 cm


Height of equilateral triangle



⇒ Side of the triangle = 21 cm


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