Question

NEED HELP ASAPPP!!!! Get brainlist!

Answer 1

Answer:

394.9 cm

Step-by-step explanation:

The formula for a cone's surface area is A = π r ( r + √r^2 + h^2 ).

r = radius

h = height

The Pythagorean theorem, a^2 + b^2 = c^2, will be needed to find the height.

Plug in the values.

a(unknown)^2 + 6^2 = 15^2

A + 36 = 255

255 - 36 = 189

√189 ≈ 13.7

Surface area formula, plug in the values.

A = 3.14 × 6 ( 6 + √6^2 + 13.7^2 )

*PEMDAS*

A = 3.14 × 6 ( 6 + √36 + 187.69 )

A = 3.14 × 6 ( 6 + √223.69 )

A = 3.14 × 6 ( 6 + 14.95 )

A = 3.14 × 6 ( 20.96 )

A = 3.14 × 125.76

A = 394.8864

*round to nearest tenth*

A = 394.9 cm

Hope this helps! :)