Question

career math i unit 4 pre - test area, perimeter, and volu
what is the surface area of the cylinder? express the answer in terms of π.
d = 8 cm
h = 18 cm
recall the formula sa = 2πr²+2πrh
152π cm²
290π cm²
176 πcm²
792π cm²

Explanation:

Step1: Find the radius

Given $d = 8$ cm, then $r=\frac{d}{2}=\frac{8}{2}=4$ cm.

Step2: Substitute values into formula

The surface - area formula of a cylinder is $SA = 2\pi r^{2}+2\pi rh$. Substitute $r = 4$ cm and $h = 18$ cm into the formula.
$SA=2\pi\times4^{2}+2\pi\times4\times18$.
First, calculate $2\pi\times4^{2}=2\pi\times16 = 32\pi$.
Second, calculate $2\pi\times4\times18=144\pi$.

Step3: Sum the two parts

$SA=32\pi + 144\pi=176\pi$ $cm^{2}$.

Answer:

$176\pi$ $cm^{2}$