The surface area(A) of a triangular pyramid can be found using the formula:
[tex]A\text{ = }\frac{1}{2}\text{ }\times\text{ a }\times\text{ b + }\frac{3}{2}\text{ }\times b\text{ }\times\text{ s}[/tex]Given the triangular prism:
Hence, we have:
a = 3.5 m
b = 4m
s = 11.1 m
Substituting the values into the formula:
[tex]\begin{gathered} A\text{ = }\frac{1}{2}\times3.5\text{ }\times4\text{ + }\frac{3}{2}\text{ }\times\text{ 4 }\times\text{ 11.1} \\ =\text{ 7 + 66.6} \\ =\text{ 73.6 m}^2 \end{gathered}[/tex]Hence, the surface area of the pyramid is 73.6 square meter