Question 828790
P = 4s


16 = 4s


16/4 = s


4 = s


s = 4


Side length is 4 ft


a^2 + b^2 = c^2


4^2 + 4^2 = c^2


16 + 16 = c^2


32 = c^2


c^2 = 32


c = sqrt(32)


c = sqrt(16*2)


c = sqrt(16)*sqrt(2)


c = 4*sqrt(2)


The diagonal is exactly {{{4*sqrt(2)}}} units long.