Answer:
[tex]ED=32\ units[/tex]
Step-by-step explanation:
we know that
Applying the Intersecting Secant Theorem
[tex]AC*BC=EC*DC[/tex]
substitute the values
[tex](16+5)*(5)=(ED+3)*(3)[/tex]
Solve for ED
[tex](21)*(5)=(ED+3)*(3)[/tex]
[tex]35=(ED+3)[/tex]
[tex]ED=35-3=32\ units[/tex]
