# How do you calculate the perimeter of an equilateral triangle?

The side length of the triangle multiplied by $3$.
Thus, if an equilateral triangle has a side length of $2$, the perimeter is $2 + 2 + 2$ because all of its sides are $2$.
We can generalize this rule by saying that if an equilateral has side length $s$, its perimeter is $s + s + s$, which is equivalent to $3 s$, or, the side length of the triangle multiplied by $3$.