I really need help! Please help, i don't understandddd

Answer:
x is 2
Step-by-step explanation:
To solve this you have to use the Pythagoram theorem A^2+B^2=C^2. So 9+16=C^2.
25=C^2
c=5
Than since u know the radius of the circle is 3, its 5-3 so x is 2.