• FREE GMAT Exam
Know how you'd score today for $0 Available with Beat the GMAT members only code • Free Veritas GMAT Class Experience Lesson 1 Live Free Available with Beat the GMAT members only code • Free Practice Test & Review How would you score if you took the GMAT Available with Beat the GMAT members only code • 5 Day FREE Trial Study Smarter, Not Harder Available with Beat the GMAT members only code • Get 300+ Practice Questions 25 Video lessons and 6 Webinars for FREE Available with Beat the GMAT members only code • Award-winning private GMAT tutoring Register now and save up to$200

Available with Beat the GMAT members only code

• 1 Hour Free
BEAT THE GMAT EXCLUSIVE

Available with Beat the GMAT members only code

• 5-Day Free Trial
5-day free, full-access trial TTP Quant

Available with Beat the GMAT members only code

• Free Trial & Practice Exam
BEAT THE GMAT EXCLUSIVE

Available with Beat the GMAT members only code

• Magoosh
Study with Magoosh GMAT prep

Available with Beat the GMAT members only code

# On the number line, point R has coordinate r and point T has

00:00

A

B

C

D

E

## Global Stats

Difficult

On the number line, point R has coordinate r and point T has coordinate t. Is t < 0?

(1) -1 < r < 0
(2) The distance between R and T is equal to r^2

OA C

Source: Official Guide

### GMAT/MBA Expert

GMAT Instructor
Joined
22 Aug 2016
Posted:
1385 messages
Followed by:
26 members
470
BTGmoderatorDC wrote:
On the number line, point R has coordinate r and point T has coordinate t. Is t < 0?

(1) -1 < r < 0
(2) The distance between R and T is equal to r^2

OA C

Source: Official Guide
Given: On the number line, point R has coordinate r and point T has coordinate t.

Question: Is t < 0?

Let's take each statement one by one.

(1) -1 < r < 0

We do not have any information about point T. Insufficient.

(2) The distance between R and T is equal to r^2.

Certainly insufficient. T can be on either side of the number line. Insufficient.

(1) and (2) together

We know that the coordinate of point R is -1 < r < 0 and the distance between R and T is equal to r^2.

Note that if -1 < r < 0, r^2 < |r|

Thus, the coordinate of point T must also be negative. Sufficient.

Hope this helps!

-Jay
_________________
Manhattan Review GRE Prep

Locations: GRE Classes Seattle | GMAT Prep Course Hong Kong | GRE Prep San Francisco | SAT Prep Classes NYC | and many more...

### GMAT/MBA Expert

GMAT Instructor
Joined
09 Oct 2010
Posted:
519 messages
Followed by:
25 members
59
BTGmoderatorDC wrote:
On the number line, point R has coordinate r and point T has coordinate t. Is t < 0?

(1) -1 < r < 0
(2) The distance between R and T is equal to r^2

Source: Official Guide
$t\,\,\mathop < \limits^? \,\,0$
$\left( 1 \right)\,\,\, - 1 < r < 0\,\,\,\left\{ \begin{gathered} \,{\text{Take}}\,\,\left( {r,t} \right) = \left( { - 0.5,0} \right)\,\,\,\,\, \Rightarrow \,\,\,\,\,\left\langle {{\text{NO}}} \right\rangle \hfill \\ \,{\text{Take}}\,\,\left( {r,t} \right) = \left( { - 0.5, - 1} \right)\,\,\,\,\, \Rightarrow \,\,\,\,\,\left\langle {{\text{YES}}} \right\rangle \hfill \\ \end{gathered} \right.$
$\left( 2 \right)\,\,\,\left| {r - t} \right| = {r^2}\,\,\,\left\{ \begin{gathered} \,{\text{Take}}\,\,\left( {r,t} \right) = \left( {0,0} \right)\,\,\,\,\, \Rightarrow \,\,\,\,\,\left\langle {{\text{NO}}} \right\rangle \hfill \\ \,{\text{Take}}\,\,\left( {r,t} \right) = \left( { - 1, - 2} \right)\,\,\,\,\, \Rightarrow \,\,\,\,\,\left\langle {{\text{YES}}} \right\rangle \hfill \\ \end{gathered} \right.$
$\left( {1 + 2} \right)\,\,\,\,\,\left| {r - t} \right| = {r^2}\,\,\,\,\mathop \Rightarrow \limits^{{\text{squaring}}} \,\,\,\,\,{\left( {r - t} \right)^2} = {r^4}\,\,\,\,\, \Rightarrow \,\,\,\,{r^2} - 2rt + {t^2} = {r^4}\,\,\,\,\,\left( * \right)$
$- 1 < r < 0\,\,\,\,\,\, \Rightarrow \,\,\,\,{r^4} < {r^2}\,\,\,\,\mathop \Rightarrow \limits^{\left( * \right)} \,\,\,\,\, - 2rt + {t^2} = {r^4} - {r^2} < 0$
$\left. \begin{gathered} - 2rt + {t^2} < 0 \hfill \\ {t^2} \geqslant 0 \hfill \\ \end{gathered} \right\}\,\,\,\,\,\, \Rightarrow \,\,\,\, - 2rt < 0\,\,\,\,\,\,\,\mathop \Rightarrow \limits^{r\, < \,\,0} \,\,\,t < 0\,\,\,\,\,\,\, \Rightarrow \,\,\,\,\,\left\langle {{\text{YES}}} \right\rangle \,\,\,\,\,\, \Rightarrow \,\,\,\,\,{\text{SUFF}}.\,$

This solution follows the notations and rationale taught in the GMATH method.

Regards,
Fabio.

_________________
Fabio Skilnik :: www.GMATH.net (Math for the GMAT)
Course release PROMO : finish our test drive till 30/Sep with (at least) 60 correct answers out of 92 (12-questions Mock included) to gain a 70% discount!

### Top First Responders*

1 Jay@ManhattanReview 84 first replies
2 Brent@GMATPrepNow 73 first replies
3 fskilnik 50 first replies
4 GMATGuruNY 37 first replies
5 Rich.C@EMPOWERgma... 16 first replies
* Only counts replies to topics started in last 30 days
See More Top Beat The GMAT Members

### Most Active Experts

1 fskilnik

GMAT Teacher

199 posts
2 Brent@GMATPrepNow

GMAT Prep Now Teacher

166 posts
3 Scott@TargetTestPrep

Target Test Prep

118 posts
4 Jay@ManhattanReview

Manhattan Review

98 posts
5 Max@Math Revolution

Math Revolution

95 posts
See More Top Beat The GMAT Experts