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An octagon has a side length of 18 feet and an area of 806.4ft^2. find the area of a smaller octagon that has a side length of 15

An octagon has a side length of 18 feet and an area of 806.4ft^2. find the area of-example-1
User Andrew Ngo
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1 Answer

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Given side length is 15 feet

Area of octagon is:


A=2(1+\sqrt[]{2})a^2

Where

a = side length

so the area of this octagon is:


\begin{gathered} A=2(1+\sqrt[]{2})a^2 \\ =2(1+\sqrt[]{2})15^2 \\ =2*(15)^2*(1+\sqrt[]{2}) \\ =450(1+\sqrt[]{2}) \\ =1086.39 \end{gathered}

User Sanjay Sharma
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