Pavement

Calculate the length of the pavement that runs through a circular square with a diameter of 40 m if the distance of the pavement from the center is 15 m.

Correct answer:

x =  26.4575 m

Step-by-step explanation:

$$\begin{gathered} D=40\text{m} \\ h=15\text{m} \\ r=D/2=40/2=20\text{m} \\ (x/2{)}^2+h^2=r^2 \\ x=2\cdot \sqrt{r^2-h^2}=2\cdot \sqrt{20^2-15^2}=10\sqrt{7}=26.4575\text{m} \end{gathered}$$

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