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Find the surface area of the cone in terms of π.

Find the surface area of the cone in terms of π.-example-1
User Michael Allen
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1 Answer

12 votes
12 votes

Answer:

161 × pi cm²

Explanation:

we just had the question about the lateral surface area (which is the area of the "mantle" of the cone from the round bottom to the pointy top).

the whole surface area of a cone is then simply the lateral surface area plus the ground area, which is a circle.

so, we have

A = pi×r×sh + pi×r²

r = radius (remember, this is half of the diameter)

sh = slant height (the length of the "mantle" straight up from the ground to the top)

so, the surface area of our cone here is

A = pi×(14/2)×16 + pi×(14/2)² = pi×7×16 + pi×7² =

= 112×pi + 49×pi = 161 × pi cm²

User David Hobs
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