Find the area of an equilateral triangle whose sides are 4 cm.

The area of an equilateral triangle is $\frac{\sqrt{3} a^2}{4}$, where a is the side of the triangle.

Here a = 4 cm

Then, $\frac{\sqrt{3} \times 4^2}{4}=4\sqrt{3} c{m}^2$

Therefore, the area of the triangle will be $4\sqrt{3}$ cm².