Question

Help and explain

I have been here for a month and going back to the video and not understand

Answer 1

The surface area of the composite figure is 1108 square inches.

Explanation:

The surface area of the composite figure (
`A_(T)`) is equal to the sum of external faces of the rectangular and triangular prisms, all measured in square inches:

`A_(T) = 20\,in * 12\,in + 2* 5\,in * 12\,in + 2* 20\,in * 5\,in + 2* 20\,in * 11\,in + 2* (1)/(2)* 12\,in * 9\,in`

`A_(T) = 1108\,in^(2)`

The surface area of the composite figure is 1108 square inches.