Question

Find the surface area of the rectangular prism.
7 ft, 5 ft, 3 ft

Answer 1

To find the surface area of a rectangular prism, you can use the formula:

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

where \(l\), \(w\), and \(h\) are the length, width, and height of the prism, respectively.

Given the dimensions:
- \(l = 7 \text{ ft}\)
- \(w = 5 \text{ ft}\)
- \(h = 3 \text{ ft}\)

Now, let's calculate each part of the formula.

1. Calculate \(lw\):

\[
lw = 7 \times 5 = 35 \text{ ft}^2
\]

2. Calculate \(lh\):

\[
lh = 7 \times 3 = 21 \text{ ft}^2
\]

3. Calculate \(wh\):

\[
wh = 5 \times 3 = 15 \text{ ft}^2
\]

Now add these areas together:

\[
lw + lh + wh = 35 + 21 + 15 = 71 \text{ ft}^2
\]

Finally, multiply by 2 to find the surface area:

\[
\text{Surface Area} = 2 \times 71 = 142 \text{ ft}^2
\]

So, the surface area of the rectangular prism is \(\boxed{142 \text{ ft}^2}\).