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Find the surface area of a right cone that has a radius of 9 inches and a height of 12 inches. Round your answer to the nearest hundredth. The surface area is about ⬜ square inches.

User Switch
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1 Answer

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Answer:

The surface area of the right cone is:


678.58in^2

Step-by-step explanation:

The surface area of a right cone is:


A=\pi r(r+\sqrt[]{r^2+h^2})

Here, r = 9 in, and h = 12 in

so


\begin{gathered} A=9\pi(9+\sqrt[]{9^2+12^2}) \\ \\ =9\pi(9+15) \\ =216\pi \\ =678.58in^2 \end{gathered}

User Oleg Shanyuk
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