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Find the surface area of this cone. 5m 4m 20pi m2 45pi m2 36pi m2 10pi m2

User Ehm
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1 Answer

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Final answer:

The surface area of the cone is calculated using the formula A=πr2 +πrℓ, where r is the radius and ℓ is the slant height. Given r=4 and ℓ=5, the surface area is 36πm2.

Step-by-step explanation:

Calculating the Surface Area

To find the surface area of a cone, we need the formula for the lateral surface area of a cone (lateral area = πr·l; where r is the radius and l is the slant height) and the formula for the area of the base (base area = π).

The total surface area (surface area) is the sum of the lateral area and base area.

The step-by-step procedure is:

Checking your answer using the rules of significant figures is important, especially when the question provides values with a specific number of significant figures.

For example, if a radius is given as 1.2 m, the calculated area should be reported in two significant figures as well to maintain consistency with the given data (A=4.5 m²).

User Krash
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