In the xy-plane, the point (-2, -3) is the center of a circle. The point (-2, 1) lies inside the circle and the point (4, -3) lies outside the circle. If the radius r of the circle is an integer, then r =
A. 6
B. 5
C. 4
D. 3
E. 2
coordinate geo
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>There are 2 points- one is internal and the other is externalbeater wrote:In the xy-plane, the point (-2, -3) is the center of a circle. The point (-2, 1) lies inside the circle and the point (4, -3) lies outside the circle. If the radius r of the circle is an integer, then r =
A. 6
B. 5
C. 4
D. 3
E. 2
>Therefore the border of the circle should lie between those 2 points.
>Distance between centre of circle and the internal point= 4(from the formual d=Sqrt of [(a2-a1)^2 + (b2-b1)^2]
>Distance between centre of circle and the external point= 6
>So the radius is between 4 and 6 and since it is an integer
> The answer should be 5
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