Question

the area of an equilateral triangle whose perimeter is 12cm is ​

Answer 1

Given: Perimeter of the triangle is 12 cm.

To find: The area.

Answer:

Formula to find the area: √3a^2/4

Perimeter = 12 cm.

Therefore, side = 12/3 = 4 cm.

a = 4 cm.

Area of the triangle = √3*4^2/4

= √3*4 = 4√3 cm^2.

Answer 2

Answer:

4√3 cm²

Step-by-step explanation:

Given that ;

Perimeter of equilateral triangle = 12 cm

∴ Each side = $\frac{\text{Perimeter}}{3}$

Each side = 4

Now, we know that ;

Area of equilateral Δ = √3 / 4 a²

                                   = √3 / 4 * 4²

                                   = √3 * 4

                                   = 4√3

Hence, area of equilateral triangle is 4√3 cm².

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Equilateral triangle : The triangle having all the sides equal and each angle measures 60°, is called equilateral triangle.

Area of equilateral ∆ = √3 / 4 a².