Hello!
Answer:
Formula for the volume of a triangular pyramid:
V = 1/3(bh)
The base is a triangle, so b = 1/2(b · h)
Solve for the base:
b = 1/2(8 · 5)
b = 1/2(40)
b = 20 m²
Solve for the volume:
V = 1/3(20 · 9)
V = 1/3(180)
V = 60 m³.
Hope this helped you!