Answer:

Explanation:
see the attached figure to better understand the problem
we know that
segment BC is a tangent to the circle at point B ---> given problem
AB is a radius of the circle
The tangent BC is perpendicular to the radius AB
Remember that
According to the Perpendicular Tangent Theorem, tangent lines are always perpendicular to a circle's radius at the point of intersection
so
The triangle ABC is a right triangle
Applying the Pythagorean Theorem

substitute the given values

solve for x


