How do you calculate the perimeter of a triangle?

1 Answer
Dec 25, 2015

To calculate a perimeter of a triangles (the sum of the lengths of all three its sides) you have to know something about this triangle.
What is known?

Explanation:

If a triangle is given by its three sides, you just sum them up to get a perimeter.

If a triangle is given as coordinates of its three vertices on a plane, you have to calculate the lengths of its three sides by coordinates of the ends of each side and them sum up the lengths.

If you are interested in any other case of defining a triangle, please specify.