What is the surface area of the right cone below?

Question

asked Apr 17, 2020 235k views

1 Answer

Eglasius · Answer 1 · 2020-04-23T01:57:57+0000

Answer: OPTION A

Explanation:

The formula that is used to calculate the surface area of a cone is:

$SA=\pi rl+\pi r^2$

Where "r" is the radius and "l" is the slant height.

You can identify in the figure that:

$l=12units\\r=3units$

Then, you need to substitute these values into the formula
$SA=\pi rl+\pi r^2$ .

Therefore, the surface area of this right cone is:

$SA=\pi (3units)(12units)+\pi (3units)^2$

$SA=45\pi\ units^2$