I need help with this math problem

Answer:
x = 15
Step-by-step explanation:
The right angle is formed at at the tangent line and the radius
So to solve for the missing angle we can solve for x using the Pythagorean Theorem
The Pythagorean theorem states that the sum of the two legs squared equal the hypotenuse squared
Knowing this we can create an equation to solve for x
[tex]12^2+9^2=x^2[/tex]
now we solve for x
[tex]12^2=144\\9^2=81\\81+144=225\\225=x^2\\\sqrt{225} =15\\\sqrt{x^2} =x\\x=15[/tex]
So we can conclude that x = 15