Great news! We will be upgrading our calculator and lesson pages over the next few months. If you notice any issues, you can submit a contact form by clicking here.
##### Related Content

Thank you!

On behalf of our dedicated team, we thank you for your continued support. It's fulfilling to see so many people using Voovers to find solutions to their problems. Thanks again and we look forward to continue helping you along your journey!

Nikkolas and Alex
Founders and Owners of Voovers

# Perimeter of a Triangle

## The Perimeter Formula

A triangle is a polygon with three sides and three vertices. The formula for perimeter is given as:

P = a + b + c

Where P is the perimeter, and a b and c are the three side lengths. ### Example Problems

Problem 1:
What is the perimeter of a triangle with side lengths of 5, 6, and 3?

Solution:
Let’s plug the side lengths into the perimeter formula.
P = a + b + c
P = 5 + 6 + 3 = 14
The perimeter of the triangle is 14.

Problem 2:
An equilateral triangle has a perimeter measured to be 81 centimeters. What are the side lengths?

Solution:
Since an equilateral triangle has three equal sides, a = b = c. We can substitute a + b + c with 3a.
Plugging what we know into the perimeter formula, we get:
P = a + b + c
81 = 3a
a = 27, b = 27, c = 27
The three sides each have a length of 27 centimeters.

Scroll to Top