GMAT Question of the Day - Daily to your Mailbox; hard ones only

It is currently 14 Aug 2018, 14:58

Close

GMAT Club Daily Prep

Thank you for using the timer - this advanced tool can estimate your performance and suggest more practice questions. We have subscribed you to Daily Prep Questions via email.

Customized
for You

we will pick new questions that match your level based on your Timer History

Track
Your Progress

every week, we’ll send you an estimated GMAT score based on your performance

Practice
Pays

we will pick new questions that match your level based on your Timer History

Not interested in getting valuable practice questions and articles delivered to your email? No problem, unsubscribe here.

Close

Request Expert Reply

Confirm Cancel

Which of the following is the graph of the equation y = |x| for all

  new topic post reply Question banks Downloads My Bookmarks Reviews Important topics  
Author Message
TAGS:

Hide Tags

Math Expert
User avatar
V
Joined: 02 Sep 2009
Posts: 47898
Which of the following is the graph of the equation y = |x| for all  [#permalink]

Show Tags

New post 17 Dec 2017, 01:48
00:00
A
B
C
D
E

Difficulty:

  5% (low)

Question Stats:

75% (00:31) correct 25% (01:04) wrong based on 155 sessions

HideShow timer Statistics

Which of the following is the graph of the equation y = |x| for all real values of x? (Note: All graphs drawn to scale.)

Image


Attachment:
2017-12-17_1244.png
2017-12-17_1244.png [ 18.49 KiB | Viewed 4170 times ]

_________________

New to the Math Forum?
Please read this: Ultimate GMAT Quantitative Megathread | All You Need for Quant | PLEASE READ AND FOLLOW: 12 Rules for Posting!!!

Resources:
GMAT Math Book | Triangles | Polygons | Coordinate Geometry | Factorials | Circles | Number Theory | Remainders; 8. Overlapping Sets | PDF of Math Book; 10. Remainders | GMAT Prep Software Analysis | SEVEN SAMURAI OF 2012 (BEST DISCUSSIONS) | Tricky questions from previous years.

Collection of Questions:
PS: 1. Tough and Tricky questions; 2. Hard questions; 3. Hard questions part 2; 4. Standard deviation; 5. Tough Problem Solving Questions With Solutions; 6. Probability and Combinations Questions With Solutions; 7 Tough and tricky exponents and roots questions; 8 12 Easy Pieces (or not?); 9 Bakers' Dozen; 10 Algebra set. ,11 Mixed Questions, 12 Fresh Meat

DS: 1. DS tough questions; 2. DS tough questions part 2; 3. DS tough questions part 3; 4. DS Standard deviation; 5. Inequalities; 6. 700+ GMAT Data Sufficiency Questions With Explanations; 7 Tough and tricky exponents and roots questions; 8 The Discreet Charm of the DS; 9 Devil's Dozen!!!; 10 Number Properties set., 11 New DS set.


What are GMAT Club Tests?
Extra-hard Quant Tests with Brilliant Analytics

Intern
Intern
avatar
Joined: 25 Nov 2017
Posts: 4
Re: Which of the following is the graph of the equation y = |x| for all  [#permalink]

Show Tags

New post Updated on: 17 Dec 2017, 06:29
The domain of the expression is all real numbers except where the expression is undefined. In this case, there is no real number that makes the expression undefined.
(−∞,∞)

For each
x value, there is one y value.

Try x= 1,0,-1 then
Y=1,0,1

So if you plot

Graph looks like a V Shape

Answer: B

Sent from my ZUK Z2132 using GMAT Club Forum mobile app

Originally posted by banuprakash on 17 Dec 2017, 03:50.
Last edited by banuprakash on 17 Dec 2017, 06:29, edited 1 time in total.
SVP
SVP
User avatar
P
Joined: 08 Jul 2010
Posts: 2132
Location: India
GMAT: INSIGHT
WE: Education (Education)
Reviews Badge
Re: Which of the following is the graph of the equation y = |x| for all  [#permalink]

Show Tags

New post 17 Dec 2017, 05:50
Bunuel wrote:
Which of the following is the graph of the equation y = |x| for all real values of x? (Note: All graphs drawn to scale.)

Image


Attachment:
2017-12-17_1244.png



Draw the graph of the line Y=X which will be a positive sloping line passing therough origin making 45º with positive X-Axis

Flip the figure of line available below the X-axis towards upside (i.e. convert all negative values of Y into positive values of Y

We get a V shape figure

Answer: Option B


ALTERNATIVELY

Keep substituting value of x and calculate values of Y and polot all the avialble points to get the graph

@x = 0, y = 0
@x = 1, y = 1
@x = 2, y = 2
@x = -1, y = +1
@x = -2, y = +2
and so on...
ANswer:m . option B
_________________

Prosper!!!
GMATinsight
Bhoopendra Singh and Dr.Sushma Jha
e-mail: info@GMATinsight.com I Call us : +91-9999687183 / 9891333772
Online One-on-One Skype based classes and Classroom Coaching in South and West Delhi
http://www.GMATinsight.com/testimonials.html

22 ONLINE FREE (FULL LENGTH) GMAT CAT (PRACTICE TESTS) LINK COLLECTION

SC Moderator
avatar
V
Joined: 22 May 2016
Posts: 1901
Premium Member CAT Tests
Which of the following is the graph of the equation y = |x| for all  [#permalink]

Show Tags

New post 17 Dec 2017, 14:09
1
Bunuel wrote:
Which of the following is the graph of the equation y = |x| for all real values of x? (Note: All graphs drawn to scale.)

Image


Attachment:
2017-12-17_1244.png

This question can be solved in 10 seconds if this property is known:

V-shaped graph

The graph of a linear absolute value function is V-shaped.

The V-shape can be upright, upside down, or sideways.

There is only one V-shaped graph in this group.

Answer B

Plot points in two phases ("pieces")

If the V-shape is not at your fingertips, then you can plot points, but how absolute value behaves changes "regular" linear graphing.

Linear absolute value functions are written in two pieces, where y = f(x):

\(f(x) = x\), for \(x\geq{0}\)

\(f(x) = -x\), for \(x < 0\)

The first part means you must plot some x-values that are 0 and positive.

The second part means you must choose some x-values that are negative (\(x < 0\)).
[(0,0) can be included with negative x, where (-0 = 0), but that is a long story.]

A note of caution: it might seem perfectly reasonable to plot
\(y = -x\), so one point is \((5, -5)\)

That is arithmetically true, but
It is not consistent with the absolute value function where
-- the variable inside (here, \(x\)), must be considered in both +/- cases (absolute value function makes a negative value positive or non-negative).

Plot three points for both cases

1) \(y = f(x) = x\)

\((0,0), (1, 1), (2, 2)\)

2) \(y = f(x) = -x\): choose points that make the value inside the brackets negative (i.e. \(f(x)\) where \(x < 0\))

\((0,0), (-1, 1), (-2,2)\)

Now there are two straight lines in a V-shape.

Answer B
_________________

In the depths of winter, I finally learned
that within me there lay an invincible summer.

-- Albert Camus, "Return to Tipasa"

Which of the following is the graph of the equation y = |x| for all &nbs [#permalink] 17 Dec 2017, 14:09
Display posts from previous: Sort by

Which of the following is the graph of the equation y = |x| for all

  new topic post reply Question banks Downloads My Bookmarks Reviews Important topics  

Events & Promotions

PREV
NEXT


GMAT Club MBA Forum Home| About| Terms and Conditions and Privacy Policy| GMAT Club Rules| Contact| Sitemap

Powered by phpBB © phpBB Group | Emoji artwork provided by EmojiOne

Kindly note that the GMAT® test is a registered trademark of the Graduate Management Admission Council®, and this site has neither been reviewed nor endorsed by GMAC®.