#### Answer

$\left( 0.7,0 \right)$

#### Work Step by Step

Using $\left( \dfrac{x_1+x_2}{2},\dfrac{y_1+y_2}{2} \right)$ or the Midpoint Formula, the midpoint of the segment joining $\left(
-3.4,8.1
\right) \text{ and } \left(
4.8,-8.1
\right),$ is
\begin{array}{l}\require{cancel}
\left( \dfrac{-3.4+4.8}{2},\dfrac{8.1+(-8.1)}{2} \right)
\\\\=
\left( \dfrac{1.4}{2},\dfrac{0}{2} \right)
\\\\=
\left( 0.7,0 \right)
.\end{array}