Dog

The dog is tied to a chain, which is mounted in the corner of the yard. The yard is shaped like a square with a side length of 20 meters. The same length is also a dog chain. Are there places in the yard where the dog can't reach?

Result

x=

Yes

No

Step-by-step explanation:

$$\begin{gathered} a=20\text{m} \\ {u}^2=a^2+a^2=2a^2 \\ u=\sqrt{2}\cdot a=\sqrt{2}\cdot 20=20\sqrt{2}\text{m}\doteq 28.2843\text{m} \\ u>a \\ x=1 \end{gathered}$$

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