The perimeter refers to the distance around a polygon, or the sum of the lengths of all the sides. The amount of fencing needed to surround a yard would be equivalent to the perimeter of that yard (the sum of all the sides).
The perimeter of the pentagon to the right is:
9 + 7 + 4 + 6 + 5 = 31
The figure shown represents a standard baseball home plate. What is the perimeter of this figure?