Answer:
(J) 8.4
Step-by-step explanation:
Given: From the given figure, it is given that AD=11, CB=6.
To find: The value of AB.
Solution: Using the tangent-secant segment length theorem that is If a tangent segment and a secant segment are drawn to a circle from an exterior point, then the square of the measure of the tangent segment is equal to the product of the measures of the secant segment and its external secant segment.
That is:

Now, substituting the values, we have




Using the Quadratic formula, we have





Since, the value of AB cannot be negative, thus


which is the required value of AB.
Hence, option J is correct.