Answer:
5 units
Step-by-step explanation:
The radius is the distance from the centre of the circle to a point on the circumference.
Use the distance formula to calculate the radius r
r = √ (x₂ - x₁ )² + (y₂ - y₁ )²
with (x₁, y₁ ) = (- 3, 2) and (x₂, y₂ ) = (1, 5)
r = 
= 
= 
= 
= 5
