Answer
$d\approx 5.83
\text{ units}
$
Work Step by Step
Using $d=\sqrt{(x_1-x_2)^2+(y_1-y_2)^2}$ or the Distance Formula, then the distance, $d$, between the given points $(
1,5
)$ and $(
6,2
)$ is
\begin{array}{l}\require{cancel}
d=\sqrt{(1-6)^2+(5-2)^2}
\\\\
d=\sqrt{(-5)^2+(3)^2}
\\\\
d=\sqrt{25+9}
\\\\
d=\sqrt{34}
\\\\
d\approx 5.83
\text{ units}
.\end{array}