What is the surface area of the triangular prism? A triangular prism. The rectangular sides are 3 feet by 6 feet, 3 feet by 7.5 feet, and 3 feet by 4.5 feet. The triangular sides have a base of 6 feet and height of 4.5 feet.

90 Feet

Step-by-step explanation:

This question is wrong, for a triangular prism to exist, it must either have a triangular base, or a square / rectangular base, but the dimensions you've given are 3x6, 3x7.5, 3x4.5, all different ...

If we're to just go by triangular sides, we can do it.

Square base =

6x6 = 36

Triangular SA = (6x4.5) / 2 = 13.5

SA = 36 + (13.5x4)

= 90 Feet