Answer:
5
Step-by-step explanation:
[tex] \triangle CDE \sim\triangle FGH...(given) [/tex]
[tex] \therefore \frac{CD}{FG}=\frac{CE}{FH}...(csst)[/tex]
[tex] \therefore \frac{4x}{28}=\frac{25}{35}[/tex]
[tex] \therefore \frac{x}{7}=\frac{5}{7}[/tex]
[tex] \therefore x=\frac{7\times 5}{7}[/tex]
[tex] \therefore x=5[/tex]