It's been a while since I've posted actively, but here is a new puzzle for the community. Good luck and I hope you enjoy it!

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... .... --- .-- / - .... . -- / - .... . / .. -- .- --. . .-.-.- .-.-.- .-.-.-

[![enter image description here][1]][1]

> <kbd>2, 5</kbd>, <kbd>1, 8</kbd>, <kbd>3, 4</kbd>, <kbd>1, 3</kbd>, <kbd>3, 6</kbd>, <kbd>1, 5</kbd>, <kbd>2, 6</kbd>, <kbd>1, 3</kbd>, <kbd>1, 10</kbd>, <kbd>1, 9</kbd>, <kbd>1, 8</kbd>, <kbd>3, 6</kbd>, <kbd>1, 5</kbd>, <kbd>1, 10</kbd>, <kbd>2, 6</kbd>, <kbd>1, 8</kbd>
>
> rkcynva gur cbfvgvba bs cv
>
> Preceding
>
> [![explain][2]][2]
>
> [Only Use...][3]

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What am I asking, and what is the answer?

  [1]: https://i.sstatic.net/9w9vu.png
  [2]: https://i.sstatic.net/hePdy.png
  [3]: https://www.khanacademy.org/math/basic-geo/basic-geometry-pythagorean-theorem/geo-pythagorean-theorem/v/the-pythagorean-theorem