It is currently 17 Nov 2017, 10:25

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

Events & Promotions

Events & Promotions in June
Open Detailed Calendar

AC is a diameter of the circle and B is a point on the circle. ACD is

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

Hide Tags

Expert Post
Math Expert
User avatar
V
Joined: 02 Sep 2009
Posts: 42250

Kudos [?]: 132494 [0], given: 12323

AC is a diameter of the circle and B is a point on the circle. ACD is [#permalink]

Show Tags

New post 17 Oct 2017, 23:39
Expert's post
1
This post was
BOOKMARKED
00:00
A
B
C
D
E

Difficulty:

  45% (medium)

Question Stats:

71% (01:08) correct 29% (01:13) wrong based on 38 sessions

HideShow timer Statistics

Image
AC is a diameter of the circle and B is a point on the circle. ACD is a straight line. What is the value of x?

(1) AB = BC
(2) x = 2y


[Reveal] Spoiler:
Attachment:
2017-10-18_1037.png
2017-10-18_1037.png [ 14.65 KiB | Viewed 747 times ]
[Reveal] Spoiler: OA

_________________

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

Kudos [?]: 132494 [0], given: 12323

Manager
Manager
User avatar
S
Joined: 05 Dec 2016
Posts: 223

Kudos [?]: 24 [0], given: 48

Concentration: Strategy, Finance
GMAT 1: 620 Q46 V29
GMAT ToolKit User
AC is a diameter of the circle and B is a point on the circle. ACD is [#permalink]

Show Tags

New post 17 Oct 2017, 23:54
(1) following to properties of right triangles, if AC is diameter then angle ABC = 90 ===> side angles BAC=BCA=x are 45.

(2) since we don't know if AB=BC we cannot define the value of angle x


Answer A.

Last edited by Alexey1989x on 19 Oct 2017, 00:58, edited 1 time in total.

Kudos [?]: 24 [0], given: 48

1 KUDOS received
Manager
Manager
avatar
B
Joined: 06 Aug 2017
Posts: 72

Kudos [?]: 13 [1], given: 26

GMAT 1: 610 Q48 V24
Re: AC is a diameter of the circle and B is a point on the circle. ACD is [#permalink]

Show Tags

New post 19 Oct 2017, 00:45
1
This post received
KUDOS
Alexey1989x wrote:
(1) following to properties of right triangles, if AC is diameter then angle ABC = 90 ===> side angles BAC=BCA=x are 45.
Since we don't know whether BC=CD we cannot define angle y..


Hi Alexey,

The question is not asking us to find out the value of y. Its asking for value of x only.
_________________

-------------------------------------------------------------------------------
Kudos are the only way to tell whether my post is useful.

Kudos [?]: 13 [1], given: 26

Manager
Manager
User avatar
S
Joined: 05 Dec 2016
Posts: 223

Kudos [?]: 24 [0], given: 48

Concentration: Strategy, Finance
GMAT 1: 620 Q46 V29
GMAT ToolKit User
Re: AC is a diameter of the circle and B is a point on the circle. ACD is [#permalink]

Show Tags

New post 19 Oct 2017, 00:58
Jabjagotabhisavera wrote:
Alexey1989x wrote:
(1) following to properties of right triangles, if AC is diameter then angle ABC = 90 ===> side angles BAC=BCA=x are 45.
Since we don't know whether BC=CD we cannot define angle y..


Hi Alexey,

The question is not asking us to find out the value of y. Its asking for value of x only.



Looks like I missed the point :) Thanks for notice!

Kudos [?]: 24 [0], given: 48

Intern
Intern
avatar
B
Joined: 25 Apr 2017
Posts: 15

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

Re: AC is a diameter of the circle and B is a point on the circle. ACD is [#permalink]

Show Tags

New post 19 Oct 2017, 01:10
Bunuel wrote:
Image
AC is a diameter of the circle and B is a point on the circle. ACD is a straight line. What is the value of x?

(1) AB = BC
(2) x = 2y


[Reveal] Spoiler:
Attachment:
2017-10-18_1037.png

I think the ănswer is C. We can deduce from the question that 3d^ + a^ = 180, 2a^+ d^ = 180 -> a^ = x = 72

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

Intern
Intern
avatar
Joined: 29 Aug 2016
Posts: 15

Kudos [?]: [0], given: 2

Re: AC is a diameter of the circle and B is a point on the circle. ACD is [#permalink]

Show Tags

New post 20 Oct 2017, 21:08
(1) A diameter subtends a right angle on the circle so given AB=BC, it is an isosceles triangle with x=45 degrees.

(2) We cannot deduce x with the given information.

A is the answer


Sent from my iPhone using GMAT Club Forum

Kudos [?]: [0], given: 2

Manager
Manager
User avatar
B
Joined: 09 Aug 2017
Posts: 59

Kudos [?]: 8 [0], given: 18

Location: United States
Concentration: Technology
GMAT 1: 640 Q44 V33
GMAT 2: 630 Q47 V29
WE: Research (Investment Banking)
CAT Tests
Re: AC is a diameter of the circle and B is a point on the circle. ACD is [#permalink]

Show Tags

New post 23 Oct 2017, 18:02
I went with answer A. AB=AC implies that it is an isosceles triangle with 45 degree angles at BCA and BAC.

St2 is insufficient, CD could be extremely far away and thus making the degree of BDC smaller. We'd also need to know the angle of ABD, which we don't have.
_________________

I'd love to hear any feedback or ways to improve my problem solving. I make a lot of silly mistakes. If you've had luck improving on stupid mistakes, I'd love to hear how you did it.

Also, I appreciate any kudos.

Kudos [?]: 8 [0], given: 18

Re: AC is a diameter of the circle and B is a point on the circle. ACD is   [#permalink] 23 Oct 2017, 18:02
Display posts from previous: Sort by

AC is a diameter of the circle and B is a point on the circle. ACD is

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


GMAT Club MBA Forum Home| About| Terms and Conditions| 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®.