Answer: 10 units.
Step-by-step explanation:
The equation of the circle in Center-radius form is:
Where the center is (h,k) and "r" is the radius.
The equation of the circle given is:
You can observe that is written in Center-radius form.
Then, you can identify that:
Knowing this, you need to solve for "r" to find the lenght of the radius.
This is:
Therefore, the lenght of the radius is 10 units.