Answer:
[tex]\large\boxed{r=2\sqrt2}[/tex]
Step-by-step explanation:
The radius (r) length is equal to the distance between the center of the circle and the point on the circle.
The formula of a distance:
[tex]d=\sqrt{(x_2-x_1)^2+(y_2-y_1)^2}[/tex]
Substitute the coordinates of the given points (5, 4) and (3, 2):
[tex]r=\sqrt{(3-5)^2+(2-4)^2}\\\\r=\sqrt{(-2)^2+(-2)^2}\\\\r=\sqrt{4+4}\\\\r=\sqrt{(4)(2)}\qquad\text{use}\ \sqrt{ab}=\sqrt{a}\cdot\sqrt{b}\\\\r=\sqrt4\cdot\sqrt2\\\\\boxed{r=2\sqrt2}[/tex]
