Answer
$d=16
\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 $(
-2\sqrt{7},10
)$ and $(
4\sqrt{7},8
)$ is
\begin{array}{l}\require{cancel}
d=\sqrt{(-2\sqrt{7}-4\sqrt{7})^2+(10-8)^2}
\\\\
d=\sqrt{(-6\sqrt{7})^2+(2)^2}
\\\\
d=\sqrt{36\cdot7+4}
\\\\
d=\sqrt{252+4}
\\\\
d=\sqrt{256}
\\\\
d=\sqrt{(16)^2}
\\\\
d=16
\text{ units}
.\end{array}
