# Given the three side lengths, how can you tell if a triangle is a right triangle?

We will use the concept of the Pythagoras theorem in order to find the required answer.

## Answer: If sides of the triangle follow the Pythagoras relation then the triangle is a right-angled triangle.

Let us see how we will use the concept of the Pythagoras theorem in order to find the required answer.

**Explanation**:

Let us consider that the triangle has sides a, b, c with c being the longest side.

Now if the triangle follows the Pythagoras theorem, then it's a right-angled triangle.

That is, c^{2} = a^{2} + b^{2}