Introduction: How to Find Perimeters

Picture of How to Find Perimeters

 This is a basic tutorial on how to find the perimeter and areas of polygons, and circles.

With the help of this instructable you will be able to find the perimeter of a pentagon, square, or any other polygon. You will also learn how to find the circumference of a circle.

Step 1: Squares.

Picture of Squares.

Squares are very simple.  The formula for square is

Perimeter = s+s+s+s or Perimeter =  s.4
                                                               
s = Side

Now go to picture two.
Each side is 8 inches so now multiply 8 times the 4 sides.
8X4=32
So your perimeter is 32 inches.

Step 2: Other Polygons.

Picture of Other Polygons.

These are petty simple too.

1st you need to see if all the sides are equal or not, and how many sides there is(N).

Here are the corresponding formulas.
Equal sides: SxN
Not Equal sides: S+S+S+S you will have to add Side plus Side till you've added the number of sides there is.

S=Side
N=Number of Sides


Step 3: Circle

Picture of Circle

 Now this is a little tricky.

For this you will need to know pi, witch goes on forever but all you need to know is 3.14

The formula:
Circumference = π.D  or  R.π.2
R= Radius
D= Diameter

So for a circle with a radius of 6 you have to do 3.14
                                                                                         x6
                                                                                    _____
                                                                                      18.84
                                                                                            x2
                                                                                    _____
                                                                                      37.68        
So what if they give you a diameter, not a radius and its 12 then you will have to do 3.14
                                                                                                                                                      x 12
                                                                                                                                                    _____ 
                                                                                                                                                     37.68

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