Respuesta :

Answer:

A:

Step-by-step explanation:

Using tangent-secant theorem

AE²=(EC)(ED)

12²=(8)(8+x+10)

144=8(x+18)

144=8x+144

8x = 144-144

8x = 0

So

x = 0

Now

ED = 8+x+10

ED = 8+0+10

ED = 18