jmc

We use the distance formula: $\sqrt{(-6-2{)}^2+(-1-5{)}^2},$ so then we find that $\sqrt{64+36}=\boxed{10}$.

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We note that the points $(2,5)$, $(-6,-1)$, and $(2,-1)$ form a right triangle with legs of length 6 and 8. This is a Pythagorean triple, so the length of the hypotenuse must be $\boxed{10}$.