DS can someone explain

Expert replies

Previous Topic Next Topic

radhika1306: Master | Next Rank: 500 Posts; Posts: 144; Joined: Fri Apr 13, 2007 2:25 am

by radhika1306 » Thu Aug 30, 2007 11:48 am

If x(x - 5)(x + 2) = 0, is x negative?
(1) x2 – 7x ≠ 0
(2) x2 –2x –15 ≠ 0

Like this post

Source: Beat The GMAT — Data Sufficiency | Thu Aug 30, 2007 11:48 am

kajcha: Master | Next Rank: 500 Posts; Posts: 321; Joined: Tue Aug 28, 2007 5:42 am; Thanked: 1 times

by kajcha » Thu Aug 30, 2007 12:01 pm

From the question x = 0 or 5 or -2

Stmt 1 - x(x-7) <> 0 means x neq 0 and x neq 7 NOT SUFF

Stmt 2 - (x+3)(x-5) neq 0 means x neq -3 and x neq 5 NOT SUFF

Together x neq 0, x neq 5 so x = -2 to hold the question true. SUFF

Ans C

Like this post

ratindasgupta: Senior | Next Rank: 100 Posts; Posts: 98; Joined: Mon Jun 11, 2007 10:32 pm; Location: Mumbai

Re: DS can someone explain

by ratindasgupta » Thu Aug 30, 2007 12:06 pm

radhika1306 wrote:If x(x - 5)(x + 2) = 0, is x negative?
(1) x2 – 7x ≠ 0
(2) x2 –2x –15 ≠ 0

First of all, i'm assuming that x2 means x^2.

For x(x - 5)(x + 2) = 0, x has to be 0, 5 or -2.

1) It states that x ≠ 0 and x ≠ 7. So x could be 5 or -2. So INSUFF

2) It states that x ≠ 5 and x ≠ -3. So x could be 0 or -2. So INSUFF

Combining 1 & 2, we get that x ≠ 0 and 5. Then x must be -2. So x is negative. Answer is therefore C.

What's the OA?

Like this post

radhika1306: Master | Next Rank: 500 Posts; Posts: 144; Joined: Fri Apr 13, 2007 2:25 am

by radhika1306 » Thu Aug 30, 2007 12:54 pm

thanks

Like this post

Post new topic Post Reply

• Page 1 of 1

GMAT Course Reviews

559 reviews

1168 reviews

431 reviews

359 reviews

147 reviews

5/5

5 Star (560 Reviews)

"Target Test Prep is the closest to the official version of the GMAT exam, about 99% accuracy in terms of the quality and quantity of information. The course has excellently created singular sets of focused lessons and tests for every possible topic that one could come across in the official GMAT exam."

"The TTP course maximizes the efficiency of the time you spend studying. It will take time and effort but I could almost guarantee that if you complete the course exactly as it is laid out you will get an amazing score. They also have a very responsive team willing to help with any questions you might have."

"TTP has two things that I think no other test prep company offers: A teaching approach that reinforces understanding and an attitude that will give you the mental preparedness needed to succeed on the test. TTP gives you a deep understanding of the concept you need to know while teaching you how to think."

Write a Review