Question

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

172 in.^ 2

344 ln.^ 2

50 in.^ 2

252 in.^ 2

Answer 1

To find the surface area of a textbook with dimensions \(2 \, \text{in.} \times 14 \, \text{in.} \times 9 \, \text{in.}\), we can use the formula for the surface area of a rectangular prism:

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

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

Let's assign the dimensions as follows:
- \(l = 14 \, \text{in.}\)
- \(w = 2 \, \text{in.}\)
- \(h = 9 \, \text{in.}\)

Now we can calculate each of the products:
1. \(lw = 14 \times 2 = 28 \, \text{in.}^2\)
2. \(lh = 14 \times 9 = 126 \, \text{in.}^2\)
3. \(wh = 2 \times 9 = 18 \, \text{in.}^2\)

Now, add these areas together:
\[
lw + lh + wh = 28 + 126 + 18 = 172 \, \text{in.}^2
\]

Now multiply by 2 to find the total surface area:
\[
\text{Surface Area} = 2 \times 172 = 344 \, \text{in.}^2
\]

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

The correct answer is:
**344 in²**.