The roof of the church

The cone roof of the church has a diameter of 3 m and a height of 4 m. What is the size of the side edge of the church roof (s=?), and how many sheets of the sheet will be needed to cover the church roof?

Correct answer:

s =  4.272 m
S =  20.1313 m²

Step-by-step explanation:

$$\begin{gathered} D=3\text{m} \\ h=4\text{m} \\ r=D/2=3/2=\frac{3}{2}=1.5\text{m} \\ s=\sqrt{r^2+h^2}=\sqrt{1.5^2+4^2}=4.272\text{m} \end{gathered}$$

$S=\pi \cdot r\cdot s=3.1416\cdot 1.5\cdot 4.272=20.1313{\text{m}}^2$

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