gmat exam coordinate

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gmat exam coordinate

by rommysingh » Sat Oct 17, 2015 1:47 pm
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 =

6
5
4
3
2

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by [email protected] » Sat Oct 17, 2015 3:53 pm
Hi rommysingh,

While this questions looks a bit complex, if you draw the actual co-ordinates that are mentioned, and calculate the 'distances' between them, then the answer is fairly easy to determine. Here's how:

The circle is centered at (-2,-3). We're told that the point (-2,1) is 'inside' the circle. The 'distance from (-2,-3) to (-2,1) is 4; so the radius has to be GREATER than 4 (remember - that point is INSIDE the circle).

We're also told that the point (4,-3) is 'outside' the circle. The 'distance from (-2,-3) to (4,-3) is 6; so the radius has to be LESS than 6 (remember - that point is OUTSIDE the circle).

We're told that the radius is an INTEGER, and there's only one integer between 4 and 6.

Final Answer: B

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by Brent@GMATPrepNow » Sat Oct 17, 2015 4:28 pm
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
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