how to find the perimeter of a polygon

In geometry which is a branch of math, there are primarily two types of polygons.
(a) Regular polygons
(b) Irregular polygons

The phrase ‘perimeter of polygon’ refers to the sum of all the sides of a polygon. First let us try to understand how to find the perimeter of a polygon that is irregular.

Perimeter of irregular polygons:

An irregular polygon is the one in which the measure of all the sides of the polygon are unequal. To find the perimeter of such a polygon, there is no other way but to add the lengths of each of the sides. For that the measure of each of the sides has to be known. If the lengths of all the sides of an irregular polygon are not known, then one cannot find its perimeter.

Example 1: Find the perimeter of the following irregular polygon.

Solution:
In the above polygon all the sides of the polygon are given. Therefore the perimeter would be
= 5 + 4 + 3 + 2 + 6
= 20 inches

Example 2: Now consider the following irregular polygon.

Solution:
The perimeter of this polygon cannot be found as some of the sides are not known and there is now way by which we can calculate them as well.
Now let us learn to find the perimeter of a polygon that is regular.

Perimeter of regular polygons:

For regular polygons, the formula for finding the perimeter would be as follows:

P = n * a

Here, P = perimeter of the polygon, n = number of sides of the polygon and a = measure of the length of the side of the polygon.

In a regular polygon all the sides are of equal length. Thus if the polygon has n sides each of length a, then the perimeter would be

= a + a + a + a + …. n times
= a * n

Example : Find the perimeter of the polygon below

Solution:
We see that each of the sides of the given polygon ( an equilateral triangle in this case) is 2 inches. Therefore the perimeter would be,
P = 2 * 3 (because there are 3 sides in the given polygon)
P = 6 inches <- answer="" p="">
In general Area and Perimeter of Polygons have different methods of solution based on whether the polygon is regular or irregular. Usually there are set formulas for area and perimeter of regular polygons. However for irregular polygons there are no well defined formulas and the calculations have to be done using various methods on case to case bases.
In case of irregular polygons, all the sides of the polygon have to be given. If not, then the unknown sides have to be calculable using basic concepts of geometry. Once we find all the sides, then adding them up would give us the perimeter of the irregular polygon.
For finding the area of an irregular polygon, we divide the polygon to rectangles and triangles with known dimensions. Then add up the areas thus found.

Learning Linear Algebra

The study of linear sets of equations and the transformations they undergo together is called Linear Algebra. While Learning Linear Algebra we come across many topics like, Systems of Equations, Matrices, Determinants, Euclidean n-space, Vector Spaces and Eigen Values & Eigen Vectors. These topics can be learnt with ease using many courses offered as online course Linear Algebra.
Math Linear Algebra
In this article we shall learn in brief about system of equations and matrices. The general linear equation is given by a1x1+ a2x2+ a3x3+…..+ anxn = b; here there are n unknowns and the known numbers are x1, x2, x3…xn . The solution set of which would be given by the set of numbers s1, s2, s3….., sn such that if we equate x1= s1, x2=s2, x3=s3….., xn=sn then the equation is satisfied.

 This means that when the solution set values are substituted on the left hand side of the equation that would be equal to the value b on the right hand side.  Solving system of equations involves different methods in which use of matrices is one of them. Some of the methods are used in solving the systems of linear equations are Gaussian Elimination and Gauss-Jordan Elimination. A series of steps in this method help in solving the given equations.

Let us now take a quick look at Matrices, a matrix is a rectangular array of numbers in the form of rows and columns and each of these elements is called an ‘entry’. The size of any given matrix is denoted with n rows and m columns using nxm. For instance, 3x4 shows it is a matrix consisting of 3 rows and 4 columns.
The matrix that has only one column is called a column matrix (vector) and the one which has only one row is called a row matrix. A matrix is denoted using an upper case letter and the entries using lower case letters. The entry in the ith row and jth column is denoted as ‘aij’ when the matrix considered is ‘A’. A square matrix is the one which has equal number of rows and columns and is denotes as nxn.
In a square matrix the entries a11, a22…ann which form the numbers in a diagonal is called the main diagonal of the matrix. This article gives a very brief outline of Matrices. To learn and understand the various topics under linear algebra with ease and to get Linear Algebra homework help there are many online courses that are offered to one and all.