The solid was created by connecting two congruent square pyramids to a rectangular prism.

A rectangular prism with a length of 14 inches, width of 15 inches, and height of 15 inches. 2 square pyramids with triangular sides with a height of 18 inches.

What is the surface area of this solid?

square inches
1380
1500
1920
3000

  1920 square inches

Step-by-step explanation:

For a rectangular prism, the lateral area can be found by ...

  LA = Pl

where P is the perimeter, and l is the length.

For a square pyramid, the lateral area can be found by ...

  LA = (1/2)Ph

where P is the perimeter of the base, and h is the slant height of the triangular faces.

For a figure with a square cross section of perimeter P "capped" by square pyramids on either end, the total surface area is the sum of the lateral areas of the three components:

  SA = (Pl) + (1/2)Ph + (1/2)Ph

  SA = P(l+h) = (4×15 in)(14 +18 in) = (60)(32) in²

  SA = 1920 in²

The surface area of the solid seems to be 1920 square inches.

__

Caveat

If the figure is something other than what we have tried to describe, your mileage may vary. A diagram would be helpful.