Find out the total surface area
The formula to calculate the SA is given by
[tex]SA=2B+PL[/tex]where
B is the area of the triangular face
P is the perimeter of the triangular face
L is the length of the prism (tent)
find out B
[tex]\begin{gathered} B=\frac{1}{2}*8*5 \\ B=20\text{ m}^2 \end{gathered}[/tex]Find out P
[tex]\begin{gathered} P=8+6+6 \\ P=20\text{ m} \end{gathered}[/tex]L=10 m
substitute
[tex]\begin{gathered} SA=2(20)+20(10) \\ SA=240\text{ m}^2 \end{gathered}[/tex]