Answer
$$8.9$$
Work Step by Step
The distance $d$ between the two points $(x_{1},y_{1})$ and $(x_{2},y_{2})$ is given by
$$d=\sqrt {(x_{2}-x_{1})^{2} + (y_{2}-y_{1})^{2}}.$$
Substitute $x_{1}=-4$, $y_{1}=2$, $x_{2}=4$ and $y_{2}=-2$ and round to the nearest tenth.
$$d=\sqrt {(4-(-4))^{2}+(-2-2)^{2}}=\sqrt {64+16}=\sqrt{80}=8.9$$