Circle in XY Plane

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Circle in XY Plane

by viveksahay » Thu Sep 26, 2013 6:34 am
A circle with center O and radius 5 is shown in the xy-plane. Lines that intersect the circle in 2 points include which of the following ?
I. y = -x +1
II. y = 2x + 1
III. y = (1/2)x - 6

a) I only
b) II Only
c) I and II Only
d) I and III only
e) I, II and III

Please see the attached picture

Source GMAT Prep Exam Pack 1
OA is C
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Circle.jpg
Source: — Problem Solving |

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by theCodeToGMAT » Thu Sep 26, 2013 9:53 am
Answer {C}

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by [email protected] » Thu Sep 26, 2013 11:51 am
Hi viveksahay,

Graphing questions are a subset of Geometry and don't show up too often on Test Day (you might see 1 or 2). They're almost always easier to beat IF you DRAW a picture. In this question, I can't think of an easier way to figure out which lines intersect the circle at two points than by quickly drawing the 3 lines and "seeing" which lines intersect at 2 points.

GMAT assassins aren't born, they're made,
Rich
Contact Rich at [email protected]
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