In the xy-plane the point (-2 -3) is the centre of a circle, the point (-2, 3) lies inside the circle and the point (6,-3) lies outside the circle. If the radius r of the circle r is an integer then r=
Select:
A) 6
B) 5
C) 4
D) 7
E) 2
Can be solved without much calculations.   You are given that (-2,-3) is the center of the circle. Point (6,-3) lies inside the circle ---&gt; the radius is lesser than distance of (-2,-3) from (6,-3) ---&gt; lesser than 8 units but the radius will also be greater than the distance of (-2,-3) from (-2,3) ----&gt; greater than 6 units.   Thus the radius is &gt;6 but &lt;8and as it is an integer, the only possible value of radius = 7 units.   7 is the correct answer.
<result>D</result>
In the xy-plane the point (-2 -3) is the centre of a circle, the point (-2, 3) lies inside the circle and the point (6,-3) lies outside the circle. If the radius r of the circle r is an integer then r=