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nipunjindal91
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Quadratic Equation- sum of roots

by nipunjindal91 Tue Nov 05, 2013 3:08 am

Q. The following is a data sufficiency question.
A: x^2 + 6x - 40 = 0
B: x^2 + kx + j = 0
Which is larger, the sum of the roots of equation A or the sum of the roots of equation B?
1. j = k
2. k is negative

Now, I was able to solve the question correctly, but my doubt is regarding one of the statements mentioned in the solution for this question which reads the following-

Note: We cannot assume that j and k are integers as the problem does not state this. If we knew they were integers, then j = k = 2 since this is the only way for j to equal k in x^2 + jx + k = 0, and we could solve the problem.


Can you please help me understand the above bold text? Would highly appreciate a quick response.

Thanks.
RonPurewal
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Re: Quadratic Equation- sum of roots

by RonPurewal Tue Nov 05, 2013 9:20 am

Hi,
Please cite the original source of this problem, per the forum rules. We can't reply to problems without a citation of the original source.

Thanks.

nipunjindal91 Wrote: Would highly appreciate a quick response.


^^ This is very rude. Please don't do it again.

We answer posts from oldest to newest.
nipunjindal91
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Re: Quadratic Equation- sum of roots

by nipunjindal91 Tue Nov 05, 2013 10:15 am

Hi Ron,

The source of this problem is http://www.platinumgmat.com/gmat-practice-test/

And I never intended to be rude. Apologies, if I did something against the rules of the forum- just thought to put in a request for an early response since I have my test coming this weekend.

Thanks.
RonPurewal
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Re: Quadratic Equation- sum of roots

by RonPurewal Wed Nov 06, 2013 6:51 am

Hi,
As I mentioned, we always answer the posts in each folder from oldest to newest. So, there's no such thing as "putting in a request for an early response". We don't even see the threads until we are ready to respond to them.

Perhaps it's just a cultural thing, but, to people from the U.S., "Would highly appreciate xxxxx" appears presumptuous, even if that isn't your intention.
I don't know whether I can put a finger on it exactly, but the most important thing is probably the fact that it's a statement, not a question. ("Could you please xxxxx?" would be more polite.)
RonPurewal
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Re: Quadratic Equation- sum of roots

by RonPurewal Wed Nov 06, 2013 6:51 am

"Platinum GMAT" is a banned source on this forum, so we're going to lock this thread.
Please see the list of banned sources, in the forum rules post (= the very first post in this folder).

As for the problem in this thread -- this problem bears no resemblance to anything that would ever show up on the GMAT exam, so, if I were you, I wouldn't worry about it.