Question

Use the image to answer the question.

A cone shows a radius of 6 and hypotenuse or side as 11.

What is the surface area of the cone? Use 3.14 for pi and round to the nearest tenth, if necessary.

(1 point)

square units

1 answer

To calculate the surface area of a cone, we use the formula:

\[ \text{Surface Area} = \pi r^2 + \pi r l \]

where:

  • \( r \) is the radius of the base,
  • \( l \) is the slant height (hypotenuse), and
  • \( \pi \) is approximately 3.14.

Given:

  • Radius, \( r = 6 \)
  • Slant height, \( l = 11 \)

Now we can calculate each component:

  1. Calculate the area of the base: \[ \pi r^2 = 3.14 \times (6^2) = 3.14 \times 36 = 113.04 \]

  2. Calculate the lateral surface area: \[ \pi r l = 3.14 \times 6 \times 11 = 3.14 \times 66 = 207.24 \]

  3. Add both areas together to get the total surface area: \[ \text{Surface Area} = 113.04 + 207.24 = 320.28 \]

  4. Rounding to the nearest tenth: \[ \text{Surface Area} \approx 320.3 \text{ square units} \]

Thus, the surface area of the cone is 320.3 square units.