the forumal is to add (sum) all the sides of the polygon.
the perimter of a pentagon is outside of the the pentegon. count what is in the outside
Cl2
C2H6
etyghviugui
40 cm
It is the sum of its 4 equal sides.
measure the distance around the outside
add all of the sides together.
(pi) times (the diameter of the circle)
Perimeter = 4*1.25 = 5m
the outside of the shape
18