|
Author |
Message |
|
TAGS:
|
|
|
Manager
Joined: 18 Oct 2011
Posts: 80
Location: United States
Concentration: Entrepreneurship, Marketing
GMAT Date: 01-30-2013
GPA: 3.3
Followers: 2
Kudos [?]:
9
[0], given: 0
|
Point K = (A,0), Point G = (2A + 4, sqrt2A+ 9). Is the dista [#permalink]
 10 Jan 2013, 09:55
Question Stats:
72% (02:15) correct
27% (01:36) wrong based on 2 sessions
Point K = (A,0), Point G = (2A + 4, sqrt2A+ 9). Is the distance between point K and G prime? (1) A^2 – 5A – 6 = 0 (2) A > 2
Last edited by Bunuel on 10 Jan 2013, 16:39, edited 1 time in total.
RENAMED THE TOPIC.
|
|
|
|
|
|
|
Manager
Joined: 04 Oct 2011
Posts: 228
Location: India
Concentration: Entrepreneurship, International Business
GMAT 1: 440 Q33 V13
GMAT 2: 0 Q0 V0
GPA: 3
Followers: 0
Kudos [?]:
17
[1] , given: 44
|
Re: Point K = (A,0), Point G = (2A + 4, sqrt2A+ 9). Is the dista [#permalink]
11 Jan 2013, 19:31
1
This post received
KUDOS
Bunuel wrote: Point K = (A,0), Point G = (2A + 4, sqrt2A+ 9). Is the distance between point K and G prime?
The formula to calculate the distance between two points (x_1,y_1) and (x_2,y_2) is d=\sqrt{(x_1-x_2)^2+(y_1-y_2)^2}.
Hence, the distance between points G and K is d=\sqrt{(2A+4-A)^2+(\sqrt{2A+9}-0)^2}=\sqrt{(A+5)^2}=|A+5|
(1) A^2 – 5A – 6 = 0 --> (A-6)(A+1)=0 --> A=6 or A=-1 --> d=|A+5|=11=prime or d=|A+5|=4\neq{prime}. Not sufficient.
(2) A > 2. If A=3, then d=|A+5|=8\neq{prime} but if A=-2, then d=|A+5|=3=prime. Not sufficient.
(1)+(2) Since from (2) A > 2, then from (1) A=6, thus d=|A+5|=11=prime. Sufficient.
Answer: C.
Hope it's clear. Hi Bunuel, (2) A > 2. If A=3, then d=|A+5|=8\neq{prime} but if A=6, then d=|A+5|=11=prime. Not sufficient. Coz it is given A>2 negative numbers are not possible right?
_________________
GMAT - Practice, Patience, Persistence
Kudos if u like 
|
|
|
|
|
|
Manager
Joined: 18 Oct 2011
Posts: 80
Location: United States
Concentration: Entrepreneurship, Marketing
GMAT Date: 01-30-2013
GPA: 3.3
Followers: 2
Kudos [?]:
9
[0], given: 0
|
Re: Coordinate Geometry [#permalink]
10 Jan 2013, 11:20
Just to be clear the whole y coordinate for point G "2A+9" is all under the square root sign
|
|
|
|
|
|
GMAT Club team member
Joined: 02 Sep 2009
Posts: 11610
Followers: 1800
Kudos [?]:
9593
[0], given: 828
|
Re: Point K = (A,0), Point G = (2A + 4, sqrt2A+ 9). Is the dista [#permalink]
10 Jan 2013, 16:51
Point K = (A,0), Point G = (2A + 4, sqrt2A+ 9). Is the distance between point K and G prime?The formula to calculate the distance between two points (x_1,y_1) and (x_2,y_2) is d=\sqrt{(x_1-x_2)^2+(y_1-y_2)^2}. Hence, the distance between points G and K is d=\sqrt{(2A+4-A)^2+(\sqrt{2A+9}-0)^2}=\sqrt{(A+5)^2}=|A+5|(1) A^2 – 5A – 6 = 0 --> (A-6)(A+1)=0 --> A=6 or A=-1 --> d=|A+5|=11=prime or d=|A+5|=4\neq{prime}. Not sufficient. (2) A > 2. If A=3, then d=|A+5|=8\neq{prime} but if A=6, then d=|A+5|=11=prime. Not sufficient. (1)+(2) Since from (2) A > 2, then from (1) A=6, thus d=|A+5|=11=prime. Sufficient. Answer: C. Hope it's clear.
_________________
PLEASE READ AND FOLLOW: 11 Rules for Posting!!!
RESOURCES: [GMAT MATH BOOK]; 1. Triangles; 2. Polygons; 3. Coordinate Geometry; 4. Factorials; 5. Circles; 6. Number Theory
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. NEW!!!
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. NEW!!!
What are GMAT Club Tests?
25 extra-hard Quant Tests
Find out what's new at GMAT Club - latest features and updates
|
|
|
|
|
|
GMAT Club team member
Joined: 02 Sep 2009
Posts: 11610
Followers: 1800
Kudos [?]:
9593
[0], given: 828
|
Re: Point K = (A,0), Point G = (2A + 4, sqrt2A+ 9). Is the dista [#permalink]
12 Jan 2013, 04:26
shanmugamgsn wrote: Bunuel wrote: Point K = (A,0), Point G = (2A + 4, sqrt2A+ 9). Is the distance between point K and G prime?
The formula to calculate the distance between two points (x_1,y_1) and (x_2,y_2) is d=\sqrt{(x_1-x_2)^2+(y_1-y_2)^2}.
Hence, the distance between points G and K is d=\sqrt{(2A+4-A)^2+(\sqrt{2A+9}-0)^2}=\sqrt{(A+5)^2}=|A+5|
(1) A^2 – 5A – 6 = 0 --> (A-6)(A+1)=0 --> A=6 or A=-1 --> d=|A+5|=11=prime or d=|A+5|=4\neq{prime}. Not sufficient.
(2) A > 2. If A=3, then d=|A+5|=8\neq{prime} but if A=-2, then d=|A+5|=3=prime. Not sufficient.
(1)+(2) Since from (2) A > 2, then from (1) A=6, thus d=|A+5|=11=prime. Sufficient.
Answer: C.
Hope it's clear. Hi Bunuel, (2) A > 2. If A=3, then d=|A+5|=8\neq{prime} but if A=6, then d=|A+5|=11=prime. Not sufficient. Coz it is given A>2 negative numbers are not possible right? Right. It should be: (2) A > 2. If A=3, then d=|A+5|=8\neq{prime} but if A=6, then d=|A+5|=11=prime. Not sufficient. Typo edited. Thank you. +1.
_________________
PLEASE READ AND FOLLOW: 11 Rules for Posting!!!
RESOURCES: [GMAT MATH BOOK]; 1. Triangles; 2. Polygons; 3. Coordinate Geometry; 4. Factorials; 5. Circles; 6. Number Theory
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. NEW!!!
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. NEW!!!
What are GMAT Club Tests?
25 extra-hard Quant Tests
Find out what's new at GMAT Club - latest features and updates
|
|
|
|
|
|
|
Re: Point K = (A,0), Point G = (2A + 4, sqrt2A+ 9). Is the dista
[#permalink]
12 Jan 2013, 04:26
|
|
|
|
|
|
|
|
|
Similar topics |
Author |
Replies |
Last post |
|
Similar
Topics:
|
 |
|
|
In the xy plane, line l and k intersect at point (4,3). Is
|
getzgetzu |
1 |
05 Apr 2006, 03:20 |
|
|
|
|
Lines l and K lie on xy plane and intersect at point (4,3).
|
gmatinjune |
8 |
08 Aug 2006, 08:05 |
|
|
|
|
The square of 5^sqrt(2) = ? a) 5^2 b) 25^sqrt(2) c) 25
|
GK_Gmat |
6 |
17 Jul 2007, 15:37 |
|
|
|
|
line L and k intersect at point 4,3. Is the product of their
|
GMATBLACKBELT |
8 |
08 Sep 2007, 22:20 |
 |
3
|
 |
In the coordinate plane, the points F (-2,1), G (1,4), and H
|
gettinit |
25 |
21 Nov 2010, 19:47 |
|
|
|
|
|
|
close
