Question

if the perimeter of an equilateral triangle is 210 cm then what will be its area​

Answer 1

Answer:

Area ≈ 2121.76 cm²                  ≈ this sign means approximately

Step-by-step explanation:

Given:

The perimeter of an equilateral triangle = 210 cm

The area of the triangle =?

Now, Let the one side of the triangle be x

∵ the given triangle is an equilateral triangle

∴ all of the sides of the triangle will be x

Now, The perimeter of an equilateral triangle = Sum of all sides

⇒210 = x + x + x = 3x

⇒x = 210/3= 70cm

Now,

Area of the equilateral triangle = √3/4 × a²   where a= side of the triangle

                                                   = √3/4 × 70²

                                                   = √3/4 × 4900

                                                   ≈ 2121.76 cm²