Question

Find the surface area of a textbook that is 2 in. × 14 in. × 9 in. (1 point)
Responses

50 in.2
50 in. squared

344 in.2
344 in. squared

172 in.2
172 in. squared

252 in.2

Answer 1

The surface area of a textbook can be calculated by finding the sum of the areas of all its faces.

The textbook has six faces:
1. The two faces that measure 2 in. × 14 in. each have an area of 2 in. × 14 in. = 28 in² each.
2. The two faces that measure 2 in. × 9 in. each have an area of 2 in. × 9 in. = 18 in² each.
3. The two faces that measure 14 in. × 9 in. each have an area of 14 in. × 9 in. = 126 in² each.

Adding up the areas of all the faces, the total surface area is:
(28 in² + 28 in²) + (18 in² + 18 in²) + (126 in² + 126 in²) = 56 in² + 36 in² + 252 in² = 344 in².

Therefore, the correct answer is 344 in.².