Given,

Area of the equilateral triangle = 36cm²

Let us assume a be the length of the side of an equilateral triangle

We know that,

Area of an equilateral triangle = sq units

36 =

a² =

a² = 36 × 4

a² = 144

a = 12 cm

We know that,

Perimeter of an equilateral triangle = 3 × a

= 3 × 12

= 36 cm

Hence, perimeter of the given equilateral triangle is 36 cm.