Question

Help i don’t understand this question

Answer 1

828 in²

Explanation:

To find the surface area of a triangular prism, you find the area of each side and add them together.

Find the area of each rectangular side:

Side 1 : 9 × 20 = 180 in²

Side 2 : 15 × 20 = 300 in²

Side 3 : 12 × 20 = 240 in²

Find the area of the triangular sides:

Area of a Triangle =
`(1)/(2)`bh

As you can see, 9 and 12 both work as the height/base for the triangular sides, so

Δ Side 1 =
`(1)/(2)`bh =
`(1)/(2)`(9)(12) = 54

Δ Side 2 is also 54.

Add the areas of all the sides together:

180 + 300 + 240 + 54 + 54 = 828 in²