A triangle is one of the most basic shapes of geometry. It has three sides and three angles. The sum of all the three angles of a triangle is always equal to 1800. This article on how to calculate perimeter of a triangle helps you in calculating perimeter of a triangle using a simple formula.
Triangles are classified into three types depending upon the length of sides and angles that are congruent. If all the three sides and three angles of a triangle are equal in length then it is called an equilateral triangle. If any two sides and any two angles are equal then it is called an isosceles triangle and if no sides and no angles are equal then it is called a scalene triangle.
To calculate the perimeter of a triangle is to calculate the distance around the closed pane figure. The type of the triangle has no impact on the perimeter of the triangle.
The formula used for calculating perimeter of a triangle is,
Perimeter of a triangle = a + b + c
- In the above formula, a, b, c are the lengths of the sides of the triangle.
- To calculate perimeter of a triangle, you need to measure the length of each sides of a triangle using a scale.
- If you have been already given the measures of the lengths of the triangle then you need not measure them again. Just place the values in the above formula and calculate the perimeter of the circle.
- If the units of the sides are not compatible with each other then convert them into compatible units using the conversion factors available online or the using the sheets that provide conversion factors.
- You can also make use of calculators to perform calculations. As the calculations are very simple there is probably no need of using calculators.
- Online calculators are also available for calculating perimeter of a triangle. Just make sure that while entering the values in these online calculators, the measure of all the sides of a triangle are initially converted into same units. If they are not in same units then you may get wrong answers.
- If the length of any of the sides of the triangle is not specified then you need to find out the measure of that side using different methods.
- For e.g. if a triangle is a right-angled triangle and two sides of the triangle are given then you can find out the measure of the third side using Pythagoras theorem i.e. AB2 = BC2 + CA2, where AB, BC and CA are the measures of the three sides of the triangle and AB is the hypotenuse.
Example:
Suppose we want to calculate perimeter of a triangle whose sides are of length 2 m, 6.5 m and 4.4 m.
Let,
- a = 2 m
- b = 6.5 m
- c = 4.4 m
Therefore, using the above formula for calculating perimeter of a triangle,
Perimeter of a triangle = a + b + c
Perimeter of a triangle = 2 + 6.5 + 4.4
Therefore,
Perimeter of a triangle = 12 .9 m
Practice problems:
- Calculate perimeter of a triangle whose sides are of length 2.2 m, 54 cm and 3.3 m.
- Calculate perimeter of a triangle whose sides are of length 12 cm, 22 cm and 1.2 cm.
Related Content: