Question

Find the surface area of a textbook that is 2 in. × 14 in. × 9 in. 2 in. × 14 in. × 9 in.(1 point)
50 in.
2 50 in.
2
344 in.
2 344 in.
2
252 in.
2 252 in.
2
172 in.
2

Answer 1

To find the surface area of a rectangular prism (like a textbook), you can use the formula:

\[
\text{Surface Area} = 2lw + 2lh + 2wh
\]

where:
- \( l \) is the length,
- \( w \) is the width,
- \( h \) is the height.

For the given dimensions of the textbook:
- \( l = 14 \) in,
- \( w = 9 \) in,
- \( h = 2 \) in.

Now substituting these values into the formula:

\[
\text{Surface Area} = 2(14)(9) + 2(14)(2) + 2(9)(2)
\]

Calculating each term:

1. \( 2(14)(9) = 2 \times 126 = 252 \)
2. \( 2(14)(2) = 2 \times 28 = 56 \)
3. \( 2(9)(2) = 2 \times 18 = 36 \)

Now adding these values together:

\[
\text{Surface Area} = 252 + 56 + 36 = 344 \, \text{in}^2
\]

Thus, the surface area of the textbook is \( \boxed{344 \, \text{in}^2} \).