Triangle - a polygon having three sides and three angles.
How to calculate the perimeter?
The perimeter of the triangle - is the sum of the lengths of its three sides.
Denote the sides of the triangle and, b, c. Perimeter in mathematical formulas denoted by Latin letter P. So, based on the rules, P = a + b + c
Suppose we have the triangle side length a = 3 cm, b = 4 cm, c = 5 cm
To find the perimeter of the triangle - you need to add up the lengths of all its sides.
Those. R = 3 + 4 + 5
P = 12 cm
Not a difficult task, right?