The volume is given by:
V = A * H
Where,
A: area of the base
H: prism height
Clearing the area we have:
A = V / H
A = 276/10
A = 27.6 feet ^ 2
The area of the base is given by:
A = (1/2) * (b) * (h)
Where,
b: base of the triangle
h: height of the triangle
Clearing b we have:
b = (2 * A) / (h)
Substituting values:
b = (2 * 27.6) / (6.9)
b = 8 feet
Answer:
the base length is:
b = 8 feet