SLOPE

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Source: — Data Sufficiency |

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by raghavsarathy » Sun Jul 26, 2009 8:36 am
IMO - A

Statement 1.

Since the lines are parallel , the slopes are equal. Hence m= 1-m
m= 1/2
Statement1 is sufficient

Statement 2
We are only given the point of intersection. We cannot determine the slope based on the point of intersection. Hence not sufficient

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by gmat740 » Sun Jul 26, 2009 9:18 am
raghavsarathy wrote:IMO - A

Statement 1.

Since the lines are parallel , the slopes are equal. Hence m= 1-m
m= 1/2
Statement1 is sufficient

Statement 2
We are only given the point of intersection. We cannot determine the slope based on the point of intersection. Hence not sufficient
Statement 2 : gives the equation of the line which intersects. So point (2,7) must satisfy both the equation.

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by yogami » Sun Jul 26, 2009 12:42 pm
Nope slope needs two points to be calculated because m = (y1 - y2)/(x1 - x2)...so only (1) is suff and (2) is not
200 or 800. It don't matter no more.

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by raghavsarathy » Sun Jul 26, 2009 5:07 pm
gmat740 wrote:
raghavsarathy wrote:IMO - A

Statement 1.

Since the lines are parallel , the slopes are equal. Hence m= 1-m
m= 1/2
Statement1 is sufficient

Statement 2
We are only given the point of intersection. We cannot determine the slope based on the point of intersection. Hence not sufficient
Statement 2 : gives the equation of the line which intersects. So point (2,7) must satisfy both the equation.
Yes. That will be true but we cannot find the slope of the line based on that Substitute (2,7) in the eqn of the line and we still have 2 unknowns.