Given the altitude of an equilateral triangle is 12 cm, find the exact perimeter of the triangle

The altitude of an equilateral triangle bisects one of the angles and the opposite side.
So, let a be the altitude of the triangle; we have the formula  a=xsinθ, where x is the side of the triangle. Solving for x, x=a / sinθ;
a = 12 cm; θ = 60 degrees;
So, x = 
The exact perimeter of the triangle is 3x;