Answer:
x = 12
Step-by-step explanation:
Apply the Secant-Tangent theorem.
The product of the length of the secant segment and its external part equals the square of the length of the tangent segment.
(whole secant) × (external part) = (tangent)²
(x) × (3) = (6)²
3x = 6²
3x = 36
(3x)/3 = 36/3
x = 12
