Question

If the area of an equilateral triangle is 81root 3 cm^2 , find its perimeter.

Answer 1

Step-by-step explanation:

Given :

Area of an equilateral triangle is 81√3 cm².

Find :

The perimeter of an equilateral triangle.

Solution :

Area of an equilateral triangle = 81√3 cm²

$\frac{ \sqrt{3} }{4} \times (side) ^{2} = 81 \sqrt{3}$

$(side) ^{2} = \frac{81 \sqrt{3 } \times 4 }{ \sqrt{3} }$

$(side)^{2} = 81 \times 4$

$side = \sqrt{81 \times 4}$

$side = 9 \times 2$

$side = 18 \: \: cm.$

Perimeter of an equilateral triangle = 3 × side

= 3 × 18

= 54 cm.

Hence :

The perimeter of an equilateral triangle is 54 cm.

Answer 2

Step-by-step explanation:

Each of equal sides of an isosceles triangle is 2 cm greater than its height. If the base of the triangle is 12 cm, find the area of a triangle.

Please give correct answer.