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

 It is currently 19 Mar 2019, 12:10

### 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

# A figure that can be folded over along a straight line so that the re

Author Message
TAGS:

### Hide Tags

Math Expert
Joined: 02 Sep 2009
Posts: 53709
A figure that can be folded over along a straight line so that the re  [#permalink]

### Show Tags

05 Feb 2018, 06:36
00:00

Difficulty:

25% (medium)

Question Stats:

65% (00:57) correct 35% (01:17) wrong based on 109 sessions

### HideShow timer Statistics

A figure that can be folded over along a straight line so that the result is two equal halves which are then lying on top of one another with no overlap is said to have a line of symmetry. Which of the following figures has only one line of symmetry?

(A) square

(B) circle

(C) equilateral triangle

(D) isosceles triangle

(E) rectangle

_________________
examPAL Representative
Joined: 07 Dec 2017
Posts: 905
Re: A figure that can be folded over along a straight line so that the re  [#permalink]

### Show Tags

18 Feb 2018, 23:27
Bunuel wrote:
A figure that can be folded over along a straight line so that the result is two equal halves which are then lying on top of one another with no overlap is said to have a line of symmetry. Which of the following figures has only one line of symmetry?

(A) square

(B) circle

(C) equilateral triangle

(D) isosceles triangle

(E) rectangle

Since this is a very 'visual' / graphic question (and also an uncommon question), we'll either try drawing it out or just guess.
This is an Alternative approach.

Drawing a square, we can SEE that the diagonal is a 'symmetry line' as defined above:
if splits the square into two identical halves that fall exactly one on top of the other.
(A) is eliminated.
(B) is also eliminated as every diameter is a symmetry line.
(C) is eliminated as every one of the heights also splits the triangle into two identical halves.
(D) is a bit trickier so we can skip it and look at E.
(E) also has two symmetry lines: these are the lines connecting the midpoints of the sides.

So (D) must be our answer.
(It does, in fact, have only one line. If AB = AC then the height from A to BC is the only line).
_________________
Manager
Joined: 21 Aug 2017
Posts: 77
Location: United States
Schools: Oxford"20 (A)
GMAT 1: 700 Q43 V42
Re: A figure that can be folded over along a straight line so that the re  [#permalink]

### Show Tags

21 Feb 2018, 18:39
So D is obviously the right choice.

However...B is sort of tricky. With a circle of no markings (not a clock, not a compass, the top of a can, whatever)...just a circle...is any diameter different from another? With no relativity, isn't there just 1 diameter? I realize this is a tree falling in the woods scenario, but it was enough to give me some pause to think if this was some sort of trick question.
Manager
Joined: 14 Oct 2017
Posts: 247
GMAT 1: 710 Q44 V41
Re: A figure that can be folded over along a straight line so that the re  [#permalink]

### Show Tags

06 Apr 2018, 14:10
jsheppa wrote:
So D is obviously the right choice.

However...B is sort of tricky. With a circle of no markings (not a clock, not a compass, the top of a can, whatever)...just a circle...is any diameter different from another? With no relativity, isn't there just 1 diameter? I realize this is a tree falling in the woods scenario, but it was enough to give me some pause to think if this was some sort of trick question.

Hi jsheppa,

if you analyze the question and the answers it becomes clear that there can be different lines of symetry even if they have the same length. In a circle there is an infinite number of symetry lines.

What makes it even clearer that if you analyze the rectangle and the square you see that they have two diagonals with the same length and that these function as two different symetry lines. If lines with equal length would be treated as one symetry lines, we would have atleast 3 answers with one symetry line, right?

Hence, it is clear that different lines can have the same length.

I hope that helps
_________________

My goal: 700 GMAT score - REACHED | My debrief - first attempt 710 (Q44,V41,IR7)

Re: A figure that can be folded over along a straight line so that the re   [#permalink] 06 Apr 2018, 14:10
Display posts from previous: Sort by