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Find the area of the roof of the gazebo in problem 25, if each roof ridge is 10ft long, as shown

Find the area of the roof of the gazebo in problem 25, if each roof ridge is 10ft-example-1
User Adaliz
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1 Answer

4 votes

Check the picture below.

first off let's check what "h" is in the triangular face.


\textit{using the pythagorean theorem} \\\\ c^2=a^2+b^2 \qquad \begin{cases} c=\stackrel{hypotenuse}{10}\\ a=\stackrel{adjacent}{6}\\ b=\stackrel{opposite}{h}\\ \end{cases}\implies 10^2=6^2+h^2 \\\\\\ 10^2-6^2=h^2\implies √(10^2-6^2)=h\implies 8=h

so, the gazebo has 4 squarish faces, each 12x12, recall 48 ÷ 4 = 12, and it has 4 triangular faces, each with a height of 8 and a base of 12.

notice we're skipping the top and bottom of the cube and the bottom of the pyramid because they're not part of the "surface area".


\stackrel{\textit{\large Areas}}{\stackrel{\textit{4 triangular faces}}{4\left[\cfrac{1}{2}(12)(8) \right]}~~~~+~~~~\stackrel{\textit{4 squarish faces}}{4[12\cdot 12]}}\implies 192+576\implies 768

Find the area of the roof of the gazebo in problem 25, if each roof ridge is 10ft-example-1
User Katalina
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