Question

5.
12.8 ft
9 ft
9 ft

Answer 1

what do we have to solve? surface area? volume?

Answer 2

9 x 9 = 81

9 x 12.8 x 1/2 (basically just dividing by 2) = 57.6(area of 1 triangle), 57.6 x 4(there are 4 sides of triangles) = 230.4

Let's add all the given areas:

81 + 230.4 = 311.4 ft^2