Given that BD is parallel to AE, then triangles CBD and CAE are similar. In consequence, their corresponding sides are in proportion, that is,
[tex]\frac{BC}{AC}=\frac{DC}{EC}[/tex]
Substituting with data and solving for ED, we get:
[tex]\begin{gathered} \frac{25}{52+25}=\frac{22.5}{ED+22.5} \\ \frac{25}{77}=\frac{22.5}{ED+22.5} \\ 25\cdot(ED+22.5)=22.5\cdot77 \\ ED+22.5=\frac{1732.5}{25} \\ ED=69.3-22.5 \\ ED=46.8\text{ m} \end{gathered}[/tex]
