Surface area of a square pyramid is given as:
[tex]\begin{gathered} \text{Surface area = }Area\text{ of base + }\frac{1}{2}PS \\ \text{where P = perimeter of base} \\ S\text{ = slant height} \end{gathered}[/tex][tex]\begin{gathered} \text{Area of base = area of square} \\ \text{Area of base = }(length)^2 \\ \text{length = 8 }ft \\ \text{Area of base = 8}^{\text{ 2}}=64ft^2 \end{gathered}[/tex][tex]\begin{gathered} \text{Perimeter of base = 4(length)} \\ \text{Perimeter of base = 4(8) = 32 ft} \end{gathered}[/tex][tex]\begin{gathered} \text{slant height = }11\text{ ft} \\ \\ \text{The surface area = 64 + }\frac{1}{2}(32\times11) \\ \\ \text{The surface area = 64 + }\frac{1}{2}(352) \end{gathered}[/tex][tex]\begin{gathered} \text{The surface area = 64 + 176} \\ \text{The surface area = }240ft^2 \end{gathered}[/tex]