Circle C and line K lie in the xy plane.

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Circle C and line K lie in the xy plane.

by andy123 » Tue Oct 13, 2009 6:06 am
I have a tough time with questions on co-ordinate geometry because I dont know what to look for in the question..pls help!!


This one is from GMAT Prep

Circle C and line K lie in the xy plane. If circle C is centered at the origin and has radius 1 , does line K intersect circle C??

(1) The x intercept of line k is greater than 1
(2) The slope of line K is -1/10

what should be the approach in this case ?

equation or diagram...

another question is it says line K ... can we interpret it as since we do not know that the line is finitie or infinite...thus answer is E ??
Source: — Data Sufficiency |

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andy123 wrote:I have a tough time with questions on co-ordinate geometry because I dont know what to look for in the question..pls help!!


This one is from GMAT Prep

Circle C and line K lie in the xy plane. If circle C is centered at the origin and has radius 1 , does line K intersect circle C??

(1) The x intercept of line k is greater than 1
(2) The slope of line K is -1/10

what should be the approach in this case ?

equation or diagram...

another question is it says line K ... can we interpret it as since we do not know that the line is finitie or infinite...thus answer is E ??

For such simple situations , go with a diagram.
You wont have to solve anything.
If you know the slope of a line and a point that falls on it your line is completely defined, so is circle with center and radius information. So the two statements together can answer this.

I normally assume an infinite line because that is pretty much the assumption in geometry/co-ord.

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by ershovici » Tue Oct 13, 2009 7:46 am
Answer is E.
St. 1 - insufficient - we do not know lines's paths.
St. 2 - insufficient - we can have a lot of equoitons and lines that satisfy this statement.
St. 1+2 - again insufficient - we can not get y intercept of the line, so can't answer a question.

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by mridul_dave » Tue Oct 13, 2009 10:06 am
ershovici wrote:Answer is E.
St. 1 - insufficient - we do not know lines's paths.
St. 2 - insufficient - we can have a lot of equoitons and lines that satisfy this statement.
St. 1+2 - again insufficient - we can not get y intercept of the line, so can't answer a question.
If you know the slope, you know the Y intercept.

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by Talkativetree » Tue Oct 13, 2009 6:08 pm
How would you solve for the y-intercept, when you're not even sure what the line actually looks like?

the X-intercept could be 10, 100, ... n, so that the y-intercept would be 1, 10, ...etc.