Question

1. what is the radius of a circle if its center is (-3,-2) and one point on the circle is (5,-2)?

√80
8
√20
64

Explanation:

Step1: Use distance formula for radius

The radius is the distance between center $(-3,-2)$ and point $(5,-2)$. Distance formula: $r=\sqrt{(x_2-x_1)^2+(y_2-y_1)^2}$

Step2: Substitute coordinates into formula

$x_1=-3,x_2=5,y_1=-2,y_2=-2$. So $r=\sqrt{(5-(-3))^2+(-2-(-2))^2}=\sqrt{(8)^2+(0)^2}=\sqrt{64}=8$

Answer:

B. 8