DS ..

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DS ..

by gabriel » Tue May 29, 2007 2:55 am
4)In the xy-plane, line L passes through point (1,p). Does L have a positive slope?
1). L passes through point (-p, 13)
2). L passes through point (0,1)

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Re: DS ..

by gabriel » Tue May 29, 2007 3:00 am
gabriel wrote:4)In the xy-plane, line L passes through point (1,p). Does L have a positive slope?
1). L passes through point (-p, 13)
2). L passes through point (0,1)

PS .. this question has been moved from PS section

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by f2001290 » Tue May 29, 2007 5:22 am
I am going with E.

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Re: DS ..

by jayhawk2001 » Tue May 29, 2007 9:31 pm
gabriel wrote:4)In the xy-plane, line L passes through point (1,p). Does L have a positive slope?
1). L passes through point (-p, 13)
2). L passes through point (0,1)
One more E

1 - Insufficient. slope = p-13 / 1+p. Need value of p to evaluate slope

2 - Insufficient. slope = p-1. Again need p.

1 & 2 together insufficient.

slope of line connecting (-p,13) and (0,1) = -12/p. This should be
equal to slope in either 1 or 2.

-12/p = p-1 implies p^2 - p + 12 = 0. No solution exists. This proves
that there cannot be a line that passes through these points and
hence E.

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by gabriel » Wed May 30, 2007 8:32 am
... yup .. E for me too...