we know that
The surface area of a triangular prism is equal to
SA=2B+PL
where
B is the area of the triangular face
P is the perimeter of the triangular face
L is the length of the prism
step 1
Find the area B
B=(1/2)*y*h
substitute the given values
B=(1/2)*11*4
B=22 units^2
step 2
Find teh value of P
P=X+X+y
substitute the given values
P=7+7+11
P=25 units
step 3
Find the surface area
SA=2*22+25*14
SA=394 units^2