Perimeter of a Triangle Calculator

This Perimeter of a Triangle Calculator helps you find the total distance around a triangle when the lengths of all three sides are known. It uses the formula P = a + b + c, where a, b, and c are the side lengths, and the answer is written in units. Add the three side lengths together to get the perimeter. It is a simple way to check answers, understand the triangle perimeter formula, and practise basic geometry step by step.

In the diagram, the sides are labeled a, b, and c.

Step-by-step method

1. Identify what is given.
2. Write the formula.
3. Substitute the values and add the side lengths.

Formula:

Example 1:

Step 1 - Identify what is given.

In this problem: The given side lengths are \(a = 3\), \(b = 4\), and \(c = 5\).

Step 2 - Write the formula.

In this problem: Use the triangle perimeter formula: \(P = a + b + c\).

Step 3 - Substitute the values and add the side lengths.

In this problem: Substitute \(a = 3\), \(b = 4\), and \(c = 5\): \(P = 3 + 4 + 5 = 12\).

Final answer:

Example 2:

Step 1 - Identify what is given.

In this problem: The given side lengths are \(a = 6.5\), \(b = 5\), and \(c = 4.25\).

Step 2 - Write the formula.

In this problem: Use the triangle perimeter formula: \(P = a + b + c\).

Step 3 - Substitute the values and add the side lengths.

In this problem: Substitute \(a = 6.5\), \(b = 5\), and \(c = 4.25\): \(P = 6.5 + 5 + 4.25 = 15.75\).

Final answer: