\(LSA = 2A_s + A_d\), the lateral surface area is the sum of the area of two square sides \(2A_s\) and the area of the diagonal side \(A_d\).

Diagonals of a square is \(s\sqrt{2}\), where \(s\) is the side.

\(A_s = 6x 6 = 36\)

\(A_d = 6(6\sqrt{2}) = 36\sqrt{2}\)

\(LSA = 2(36) +36\sqrt{2} \)

\(LSA = 122.91~ft^2\)