The length of each side of the sign is 6in
The perimeter of a polygon is obtained by adding all the sides of the polygon. The polygon is a regular polygon
Also the polygon that is cut out is a regular Pentagon, therefore the perimeter of the Pentagon = 5x
The perimeter of the Pentagon sign = 30inches
30 = 5x
where x is each side length
x = 30/5
x = 6
Therefore, the length of each side of the sign is 6in