A spyglass in the shape of a cone has a slant height of 18 centimeters and a radius of 6 centimeters. What is the surface area of the spyglass? Use 3.14 for pi.(1 point) Responses 339.12 square centimeters 339.12 square centimeters 1,356.48 square centimeters 1,356.48 square centimeters 452.16 square centimeters 452.16 square centimeters 197.82 square centimeters

1 answer

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

\[ \text{Surface Area} = \pi r (r + l) \]

where \( r \) is the radius, \( l \) is the slant height, and \( \pi \) is approximately 3.14.

Given:

  • Radius (\( r \)) = 6 cm
  • Slant height (\( l \)) = 18 cm

Now, substituting the values into the formula:

\[ \text{Surface Area} = 3.14 \times 6 \times (6 + 18) \]

First, calculate \( (6 + 18) = 24 \).

Now substitute this into the formula:

\[ \text{Surface Area} = 3.14 \times 6 \times 24 \]

Calculating \( 3.14 \times 6 = 18.84 \).

Now, multiply by 24:

\[ \text{Surface Area} = 18.84 \times 24 = 452.16 \text{ square centimeters} \]

Thus, the surface area of the spyglass is 452.16 square centimeters.