Square has 4 sides that are each 12 feet long, therefore the total perimeter of the square is 48. (12+12+12+12 or 12x4)
Hexagon has 6 sides. If each side is equal to another, the total perimeter of the square must equal the total perimeter of the hexagon.
Perimeter = 48. Hexagon with 6 sides, therefore you divide 48/6 to find the length of each side. In this case, 48/6 = 8.
So, each side of the hexagon tablecloth is 8 feet long.