College

The volume of a cone with a radius of 7 cm is [tex]$147 \pi$[/tex] cubic centimeters. Which expression can be used to find [tex]$h$[/tex], the height of the cone?

A. [tex]$147 \pi = \frac{1}{3}(7)(h)^2$[/tex]

B. [tex]$147 \pi = \frac{1}{3} \pi \left(7^2\right)(h)$[/tex]

C. [tex]$147 \pi = \frac{1}{3} \pi h$[/tex]

D. [tex]$147 \pi = \frac{1}{3} \pi(7)(h)$[/tex]

Answer :

To solve this problem, we need to determine which expression can be used to find the height [tex]\( h \)[/tex] of a cone given its volume and radius.

### Step-by-Step Solution:

1. Understand the Formula:
The volume [tex]\( V \)[/tex] of a cone is given by the formula:
[tex]\[
V = \frac{1}{3} \pi r^2 h
\][/tex]
where [tex]\( r \)[/tex] is the radius of the cone, [tex]\( h \)[/tex] is the height, and [tex]\( \pi \)[/tex] is a constant.

2. Substitute the Given Values:
We are given:
- Volume [tex]\( V = 147 \pi \)[/tex] cubic centimeters
- Radius [tex]\( r = 7 \)[/tex] cm

Substitute these values into the volume formula:
[tex]\[
147 \pi = \frac{1}{3} \pi (7)^2 h
\][/tex]

3. Simplifying the Expression:
To find the expression for height [tex]\( h \)[/tex], we can focus on:
- Squaring the radius: [tex]\( 7^2 = 49 \)[/tex]
- Substitute into the volume equation:
[tex]\[
147 \pi = \frac{1}{3} \pi \times 49 \times h
\][/tex]

4. Set Up to Solve for [tex]\( h \)[/tex]:
The expression simplifies to:
[tex]\[
147 \pi = \frac{1}{3} \pi \times 49 \times h
\][/tex]

5. Identify the Correct Option:
This matches the expression given in one of the options:
[tex]\[
147 \pi = \frac{1}{3} \pi \left(7^2\right) (h)
\][/tex]

Thus, the correct expression from the provided options is:
[tex]\[
147 \pi = \frac{1}{3} \pi (7^2) h
\][/tex]

By following these steps, we determined that this expression can be used to find the height [tex]\( h \)[/tex] of the cone.