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Help me find the lateral and the surface area I have to round to the nearest tenths if necessary

Help me find the lateral and the surface area I have to round to the nearest tenths-example-1
User Dagrada
by
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1 Answer

3 votes

Answer:

L.A. = 188.4 m²

S.A. = 266.9 m²

Explanation:

The formula of a lateral area of a cone:


L.A.=\pi rs

r - radius

s - slant height

We have r = 5m and s = 12m. Substitute:


L.A.=\pi(5)(12)=60\pi\ m^2\\\\\pi\approx3.14\to L.A.\approx(60)(3.14)=188.4\ m^2

The formula of a surface area of a cone:


S.A.=\pi r(r+s)

Substitute:


S.A.=\pi(5)(5+12)=\pi(5)(17)=85\pi\ m^2\approx(85)(3.14)=266.9\ m^2

User Junia
by
6.9k points
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