ANSWER:

Explanation:
We have that the sides EB and ED are equal, therefore ED measures 24 units.
Therefore, a right triangle is formed where the legs are ED and EC and the hypotenuse is DC.
We apply the Pythagorean theorem which is the following:

In this case would be:
![\begin{gathered} DC^2=ED^2+EC^2 \\ DC^2=24^2+80^2 \\ DC^2=576+6400 \\ DC=\sqrt[]{6976} \\ DC=83.5 \end{gathered}](https://img.qammunity.org/2023/formulas/mathematics/college/er912a09egeh4qh51mahxtwpm10qcnnm2d.png)