Question

Find the surface area of a textbook that is 2 in. × 14 in. × 9 in.
a. 172 in.^2
b. 252 in.^2
c. 344 in.^2
d. 50 in.^2

Answer 1

To find the surface area of the textbook, you need to find the area of each face and then add them together.

The dimensions of the textbook are given as 2 in. (length) × 14 in. (width) × 9 in. (height).

The area of the top face is 2 in. × 14 in. = 28 in.²
The area of the bottom face is also 2 in. × 14 in. = 28 in.²

The area of the front face is 2 in. × 9 in. = 18 in.²
The area of the back face is also 2 in. × 9 in. = 18 in.²

The area of the left side face is 14 in. × 9 in. = 126 in.²
The area of the right side face is also 14 in. × 9 in. = 126 in.²

Therefore, the total surface area of the textbook is 28 in.² + 28 in.² + 18 in.² + 18 in.² + 126 in.² + 126 in.² = 344 in.²

So the correct option is c. 344 in.²