Answer:
AC = 10
Step-by-step explanation:
We can apply the properties of two secants intersecting outside a circle
(see attached for reference).
in our case, our formula will be
BC (BC + AB) = CD (CD + DE), which can be written as:
BC · AC = CD · CE
We are given:
BC = 6, DC = CD = 5, CE = 12
simply substitute the known values into the equation above
6 · AC = 5 · 12
AC = (5)(12) / 6
AC = 10
