Triangle is a 3 sided closed figure and it consists of 3 angles formed from the 3 sides. There are different types of triangles based on their side lengths and the measure of the angles in the triangle. The two important formulas involving triangles is the formula to calculate the area of the triangle and the formula to calculate the perimeter of the triangle. The area of a triangle is 1/2 times the product of the base of the triangle and its height. The perimeter is the sum of all the sides of the triangle.
Example 1: Calculate the area of the triangle whose base length is 20cm and height is 5 cm.
Area of the triangle is given by the formula, Area = ½ * (Base) * (Height)
In the given question, base of the triangle, b = 20cm
Height of the triangle, h = 5cm
Therefore we get, Area of the triangle, A = 1/2 * 20cm * 5cm ==> Area, A = 50cm2
Hence area of the given triangle, A = 50cm2
Example 2: Calculate the perimeter of the triangle ABC if the lengths of the sides are given as follows: AB = 6m, BC = 8m and AC = 10m.
Perimeter of the triangle is given by the formula, Perimeter = Sum of all the sides of the triangle.
This implies: Perimeter of triangle ABC = AB + BC + AC
Given: length of the side AB = 6m, BC = 8m and AC = 10m
Therefore we get: Perimeter, P = 6 + 8 + 10 = 24m
Hence perimeter of the triangle ABC, P = 24m