Check GMAT Club Decision Tracker for the Latest School Decision Releases https://gmatclub.com/AppTrack

 It is currently 29 May 2017, 03:58

### 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

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

# Events & Promotions

###### Events & Promotions in June
Open Detailed Calendar

# What is the difference between the lengths of diagonals of

Author Message
TAGS:

### Hide Tags

CEO
Joined: 21 Jan 2007
Posts: 2741
Location: New York City
Followers: 11

Kudos [?]: 942 [2] , given: 4

What is the difference between the lengths of diagonals of [#permalink]

### Show Tags

15 Nov 2007, 08:43
2
KUDOS
4
This post was
BOOKMARKED
00:00

Difficulty:

25% (medium)

Question Stats:

76% (02:16) correct 24% (01:14) wrong based on 149 sessions

### HideShow timer Statistics

What is the difference between the lengths of diagonals of parallelogram ABCD (BD > AC)

(1) AB - BC = 2
(2) Angle ABC = 30 degrees
[Reveal] Spoiler: OA
Director
Joined: 22 Mar 2011
Posts: 612
WE: Science (Education)
Followers: 101

Kudos [?]: 948 [2] , given: 43

Re: What is the difference between the lengths of diagonals of [#permalink]

### Show Tags

25 Jul 2012, 05:50
2
KUDOS
1
This post was
BOOKMARKED
teal wrote:
What is the difference between the lengths of diagonals of parallelogram $$ABCD$$ ( $$BD \gt AC$$ )?

$$AB - BC = 2$$
$$\angle ABC = 30$$ degrees

OA:E

Here is my reasoning -

A) Difference between two diagonals does not restrict the shape of the quad. If it's shape is closer to rectangle then diff between diagonals is very less as opposed to if you change the quad's shape to move away from being a rectangle. ( Rectangle has equal diags.) - Insuff.

B) One angle =30. Due to the property of Parallelogram, this restricts the other angles to 30, 150, 30 (opp angles equal and adjacent angles supplementary). So we have a definite shape for parallelogram but NOT a fixed size so we can still vary the size. As size will vary, the difference between diagonals should also vary -

Here is my question for Forum moderators - as the size of parallelogram will increase will the difference between it's diagonals also increase , right?? vice versa for decrease???? Please confirm.

For C -

You can still vary the size of the quad, so the difference in diagonals should vary, hence E.

For B:
Given one angle of the parallelogram, all its angles are determined as you mentioned.
So, the "shape" of the parallelogram is uniquely determined, meaning all of them are similar, they are just "smaller" or "larger".
Similarity also means the lengths of the sides and the diagonals (which can also be seen as sides in some triangles, like half of the parallelogram) increase or decrease proportionally, so their difference cannot remain a constant.

For C:
Please, refer to the attached drawing, where y in fact is $$2x+2-x\sqrt{3}$$.
The diagonals then can be expressed in terms of x, but we don't have any specific value for x.

Attachments

Parallelogram30.jpg [ 11.92 KiB | Viewed 3619 times ]

_________________

PhD in Applied Mathematics
Love GMAT Quant questions and running.

Intern
Joined: 28 Aug 2007
Posts: 37
Followers: 0

Kudos [?]: 4 [0], given: 0

Re: What is the difference between the lengths of diagonals of [#permalink]

### Show Tags

15 Nov 2007, 09:02
bmwhype2 wrote:
What is the difference between the lengths of diagonals of parallelogram ABCD (BD > AC)

1. AB - BC = 2
2. Angle ABC = 30 degrees

E you can keep all points ABC in place and move point B around to achieve any difference in length
Manager
Joined: 08 Nov 2007
Posts: 99
Followers: 1

Kudos [?]: 3 [0], given: 0

Re: What is the difference between the lengths of diagonals of [#permalink]

### Show Tags

15 Nov 2007, 09:11
antihero wrote:
bmwhype2 wrote:
What is the difference between the lengths of diagonals of parallelogram ABCD (BD > AC)

1. AB - BC = 2
2. Angle ABC = 30 degrees

E you can keep all points ABC in place and move point B around to achieve any difference in length

I dont follow - how do you move one point about but not another? If it's a parallelogram, then surely moving one point will move one of the other's if it is to maintain two parallel sides?
Manager
Joined: 08 Nov 2007
Posts: 99
Followers: 1

Kudos [?]: 3 [0], given: 0

Re: What is the difference between the lengths of diagonals of [#permalink]

### Show Tags

15 Nov 2007, 10:38
antihero wrote:
alrussell wrote:
antihero wrote:
bmwhype2 wrote:
What is the difference between the lengths of diagonals of parallelogram ABCD (BD > AC)

1. AB - BC = 2
2. Angle ABC = 30 degrees

E you can keep all points ABC in place and move point B around to achieve any difference in length

I dont follow - how do you move one point about but not another? If it's a parallelogram, then surely moving one point will move one of the other's if it is to maintain two parallel sides?

Still E

Agreed - but how do you move a single point around? Im confused.
Manager
Joined: 20 Sep 2006
Posts: 58
Followers: 1

Kudos [?]: 18 [0], given: 0

Re: What is the difference between the lengths of diagonals of [#permalink]

### Show Tags

16 Nov 2007, 06:47
bmwhype2 wrote:
What is the difference between the lengths of diagonals of parallelogram ABCD (BD > AC)

1. AB - BC = 2
2. Angle ABC = 30 degrees

I am confused to. How can diagonals of a parallelogram be different in length.
They have to be equal in length to satisfy the definition of a parallelogram which is
" A quadrilateral with both pairs of opposite sides parallel and equal in length."
Manager
Joined: 13 May 2010
Posts: 122
Followers: 0

Kudos [?]: 17 [0], given: 4

Re: What is the difference between the lengths of diagonals of [#permalink]

### Show Tags

24 Jul 2012, 20:27
What is the difference between the lengths of diagonals of parallelogram $$ABCD$$ ( $$BD \gt AC$$ )?

$$AB - BC = 2$$
$$\angle ABC = 30$$ degrees

OA:E

Here is my reasoning -

A) Difference between two diagonals does not restrict the shape of the quad. If it's shape is closer to rectangle then diff between diagonals is very less as opposed to if you change the quad's shape to move away from being a rectangle. ( Rectangle has equal diags.) - Insuff.

B) One angle =30. Due to the property of Parallelogram, this restricts the other angles to 30, 150, 30 (opp angles equal and adjacent angles supplementary). So we have a definite shape for parallelogram but NOT a fixed size so we can still vary the size. As size will vary, the difference between diagonals should also vary -

Here is my question for Forum moderators - as the size of parallelogram will increase will the difference between it's diagonals also increase , right?? vice versa for decrease???? Please confirm.

For C -

You can still vary the size of the quad, so the difference in diagonals should vary, hence E.
Director
Joined: 22 Mar 2011
Posts: 612
WE: Science (Education)
Followers: 101

Kudos [?]: 948 [0], given: 43

Re: What is the difference between the lengths of diagonals of [#permalink]

### Show Tags

25 Jul 2012, 05:00
saviop wrote:
bmwhype2 wrote:
What is the difference between the lengths of diagonals of parallelogram ABCD (BD > AC)

1. AB - BC = 2
2. Angle ABC = 30 degrees

I am confused to. How can diagonals of a parallelogram be different in length.
They have to be equal in length to satisfy the definition of a parallelogram which is
" A quadrilateral with both pairs of opposite sides parallel and equal in length."

It says "sides" and not diagonals!!!
_________________

PhD in Applied Mathematics
Love GMAT Quant questions and running.

Manager
Joined: 10 Mar 2014
Posts: 244
Followers: 2

Kudos [?]: 79 [0], given: 13

Re: What is the difference between the lengths of diagonals of [#permalink]

### Show Tags

19 Apr 2014, 11:30
teal wrote:
What is the difference between the lengths of diagonals of parallelogram $$ABCD$$ ( $$BD \gt AC$$ )?

$$AB - BC = 2$$
$$\angle ABC = 30$$ degrees

OA:E

Here is my reasoning -

A) Difference between two diagonals does not restrict the shape of the quad. If it's shape is closer to rectangle then diff between diagonals is very less as opposed to if you change the quad's shape to move away from being a rectangle. ( Rectangle has equal diags.) - Insuff.

B) One angle =30. Due to the property of Parallelogram, this restricts the other angles to 30, 150, 30 (opp angles equal and adjacent angles supplementary). So we have a definite shape for parallelogram but NOT a fixed size so we can still vary the size. As size will vary, the difference between diagonals should also vary -

Here is my question for Forum moderators - as the size of parallelogram will increase will the difference between it's diagonals also increase , right?? vice versa for decrease???? Please confirm.

For C -

You can still vary the size of the quad, so the difference in diagonals should vary, hence E.

HI,

I have couple of queries here.

1. the question is talking about parallelogram. so it can be rectangle ( can not be square or rohumbus) or parallelogram ( oppsite sites and opposite angles are equal)

so what you mean by

"Difference between two diagonals does not restrict the shape of the quad. If it's shape is closer to rectangle then diff between diagonals is very less as opposed to if you change the quad's shape to move away from being a rectangle"

Thanks.
GMAT Club Legend
Joined: 09 Sep 2013
Posts: 15509
Followers: 651

Kudos [?]: 210 [0], given: 0

Re: What is the difference between the lengths of diagonals of [#permalink]

### Show Tags

27 Jun 2016, 23:19
Hello from the GMAT Club BumpBot!

Thanks to another GMAT Club member, I have just discovered this valuable topic, yet it had no discussion for over a year. I am now bumping it up - doing my job. I think you may find it valuable (esp those replies with Kudos).

Want to see all other topics I dig out? Follow me (click follow button on profile). You will receive a summary of all topics I bump in your profile area as well as via email.
_________________
Manager
Joined: 03 Dec 2014
Posts: 130
Location: India
GMAT 1: 620 Q48 V27
GPA: 1.9
WE: Engineering (Energy and Utilities)
Followers: 2

Kudos [?]: 48 [0], given: 391

Re: What is the difference between the lengths of diagonals of [#permalink]

### Show Tags

07 Sep 2016, 04:56
bmwhype2 wrote:
What is the difference between the lengths of diagonals of parallelogram ABCD (BD > AC)

(1) AB - BC = 2
(2) Angle ABC = 30 degrees

we can't fix the shape ( parallelogram or rhomus). hence E
Re: What is the difference between the lengths of diagonals of   [#permalink] 07 Sep 2016, 04:56
Similar topics Replies Last post
Similar
Topics:
3 In a square, the length of a side is s and the diagonal is d. What is 4 17 May 2017, 07:55
1 A length of rope is cut into three different lengths. What is the leng 1 24 Nov 2016, 09:53
1 What is the length of the diagonal of rectangle ABCD? 3 20 May 2016, 14:02
27 What is the absolute difference between the cubes of two 20 21 Jan 2017, 08:03
what is the two digit number? 1. the difference between the 6 05 Dec 2011, 18:59
Display posts from previous: Sort by