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.
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.
So your perimeter is 32 inches.
Step 2: Other Polygons.
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.
N=Number of Sides
Step 3: Circle
For this you will need to know pi, witch goes on forever but all you need to know is 3.14
Circumference = π.D or R.π.2
So for a circle with a radius of 6 you have to do 3.14
So what if they give you a diameter, not a radius and its 12 then you will have to do 3.14