## Does w - v = 0?

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### Does w - v = 0?

by [email protected] » Tue Oct 18, 2022 5:43 am

00:00

A

B

C

D

E

## Global Stats

Does w - v = 0?

(1) w² - v² = 0
(2) wv < 0

Source: www.gmatprepnow.com

### GMAT/MBA Expert

GMAT Instructor
Posts: 16202
Joined: Mon Dec 08, 2008 6:26 pm
Location: Vancouver, BC
Thanked: 5254 times
Followed by:1268 members
GMAT Score:770

### Re: Does w - v = 0?

by [email protected] » Wed Oct 19, 2022 6:32 pm

00:00

A

B

C

D

E

## Global Stats

[email protected] wrote:
Tue Oct 18, 2022 5:43 am
Does w - v = 0?

(1) w² - v² = 0
(2) wv < 0

Source: www.gmatprepnow.com
Target question: Does w - v = 0?
This is a good candidate for rephrasing the target question.
If we add v to both sides of the target question, we get...
REPHRASED target question: Does w = v?

Aside: Here’s a video with tips on rephrasing the target question: https://www.gmatprepnow.com/module/gmat- ... cy?id=1100

Statement 1: w² - v² = 0
There are infinitely many values of w and v that satisfy statement 1. Here are two:
Case a: w = 3 and v = 3. In this case, the answer to the REPHRASED target question is YES, w equals v
Case b: w = 3 and v = -3. In this case, the answer to the REPHRASED target question is NO, w does not equal v
Since we can’t answer the target question with certainty, statement 1 is NOT SUFFICIENT

Statement 2: wv < 0
If wv is negative, then one value (w or v) is POSITIVE, and the other value is NEGATIVE.
Since w and v are different signs, w and v cannot be equal
Since we can answer the target question with certainty, statement 2 is SUFFICIENT