Answer:

Explanation:
1. By definition, a regular pentagon is a polygon that has five sides with equal length and five vertices.
2. As you can see in the figure attached, the lenght of a side of the pentagon is
, so, as the other sides are equal, you can obtain the perimeter by multiplying the lenght of that side by 5. Therefore, you can write the following expression:

Where
is the perimeter and
is the lenght of each side of the pentagon.