# Perimeter of an Equilateral Triangle

The **equilateral triangle** has all three sides equal, so its **perimeter** will be three times the length of one of its sides (*a*).

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Triangle-total.rar or Triangle-total.exe

Note. Courtesy of the author: **José María Pareja Marcano**. Chemist. Seville, Spain.

## Exercise

Being a **equilateral triangle** with all sides equal in length *a*=5 cm.

What is its **perimeter**?

Applying the above formula:

We obtain that the perimeter of this equilateral triangle is **15 cm**.