Question

What is the surface area of the cone? (Use 3.14 for π.)

Answer 1

To solve this problem you must apply the proccedure shown below:

1. You must apply the formula for calculate the surface area of a cone, which is:

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

Where $r$ is the radius ($r=7cm$) and $l$ is the slant height ($l=12cm$) and $\pi =3.14$

2. You need to substitute these values into the formula:

$SA=(3.14) (7cm)^{2} +(3.14)(7cm)(12cm)\\ SA=417.62cm^{2}$

Therefore, the answer is the last option: $417.62cm^{2}$