You will need
  • To know all sides of the quadrangle.
Instruction
1
In order to calculate the perimeter of quadrilateral ABCD with sides AB, BC, CD and DA, we need to put together each of its sides:

P = AB+BC+CD+DA, where

P - perimeter of the quadrilateral.
2
If given a square with side a (a square has all sides are equal), then its perimeter will be calculated thus:

P = 4*a.
How to find the perimeter of a quadrilateral
3
If given a rectangle, or a parallelogram (they're both opposite sides are equal), then its area would be calculated as follows:

P = 2*(a+b), where a and b are the sides of the rectangle/parallelogram.
How to find the perimeter of a quadrilateral