You can use the distance formula to solve this.
Distance Formula:
[tex]d = \sqrt{(X_2 -X_1)^2 + (Y_2 - Y_1)^2}[/tex]
I am going to use point (3,2) as point 1 and (-1,-4) as point 2
Insert the points into the formula
[tex]d = \sqrt{(X_2 -X_1)^2 + (Y_2 - Y_1)^2}[/tex]
[tex]d = \sqrt{((-1) - 3)^2 + ((-4) - 2)^2}[/tex]
Solve:
[tex]d = \sqrt{((-1) - 3)^2 + ((-4) - 2)^2}[/tex]
[tex]d = \sqrt{(-4)^2 + (-6)^2}[/tex]
[tex]d = \sqrt{16 + 36}[/tex]
[tex]d = \sqrt{52}[/tex]
[tex]d = \sqrt{52} = \sqrt{4}\sqrt{13}[/tex]
[tex]d = \sqrt{52} = 2 \sqrt{13}[/tex]
[tex]d = 2 \sqrt{13}[/tex]
[tex]radius = 2 \sqrt{13} = 7.2111[/tex]
