I still need help on this please

Answer:
x = [tex]\frac{85}{3}[/tex]
Step-by-step explanation:
From the figure attached,
ΔABC ~ ΔADE
Therefore, by the property of similar triangles corresponding sides of the given triangles will be proportional.
[tex]\frac{AB}{AD}=\frac{AC}{AE}=\frac{BC}{DE}[/tex]
[tex]\frac{AB}{AD}=\frac{BC}{DE}[/tex]
[tex]\frac{12}{20}=\frac{17}{x}[/tex]
x = [tex]\frac{20\times 17}{12}[/tex]
x = [tex]\frac{85}{3}[/tex]