we know that
The lateral surface area of a square pyramid is equal to the area of its four lateral triangular faces
so
[tex]\begin{gathered} LA=4\cdot\mleft\lbrace\frac{1}{2}\cdot5\cdot8\mright\rbrace \\ LA=80in^2 \end{gathered}[/tex]
therefore
the lateral area is 80 square inches
