Add the 3 sides together
Chat with our AI personalities
The sides of a triangle add up to the perimeter.
18 inches and it is an equilateral triangle
It depends on what you wish to measure: the lengths of sides, the angles, the area, the perimeter.
-- Measure or calculate the length of one side. -- Measure or calculate the length of another side. -- Measure or calculate the length of the only remaining side. -- Add the three numbers. The sum is the perimeter of the triangle.
You find the three sides of the triangle, and assure that they are all in the same unit, and then add the sides together to find the perimeter of the triangle.