The length of a side of an equilateral triangle is 21 cm. what would be the approximate area of the circumcircle of the equilateral triangle.
[Use \(\pi = \frac{22}{7}\)]
1. 154 \(\sqrt{3}\) cm2
2. 462 \(\sqrt{3}\) cm2
3. 462 cm2
4. 484 cm2
The length of a side of an equilateral triangle is 21 cm. what would be the approximate area of the circumcircle of the equilateral triangle.
[Use \(\pi = \frac{22}{7}\)]
1. 154 \(\sqrt{3}\) cm2
2. 462 \(\sqrt{3}\) cm2
3. 462 cm2
4. 484 cm2
1. 154 \(\sqrt{3}\) cm2
2. 462 \(\sqrt{3}\) cm2
3. 462 cm2
4. 484 cm2
Correct Answer – Option 3 : 462 cm2
Given:
Side of equilateral triangle = 21 cm
Formula used:
Radius of circumcircle of an equilateral triangle = side/√3
Area of circle = πr2 where, r = Radius
Calculation:
The radius of circumcircle = 21/√3
⇒ 7 × √3
⇒ 7√3 cm
Area of the circumcircle = 22/7 × 7√3 × 7√3
⇒ 22 × 7 × 3 cm2
⇒ 22 × 21 cm2
⇒ 462 cm2
∴ The approximate area of the circumcircle of the equilateral triangle is 462 cm2