It is currently 18 Oct 2017, 12:05

### 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

# Does curve (x-a)^2 + (y-b)^2 = 16 intersect the Y axis? 1.

 post reply Question banks Downloads My Bookmarks Reviews Important topics
Author Message
CEO
Joined: 21 Jan 2007
Posts: 2734

Kudos [?]: 1046 [0], given: 4

Location: New York City
Does curve (x-a)^2 + (y-b)^2 = 16 intersect the Y axis? 1. [#permalink]

### Show Tags

28 Nov 2007, 13:48
This topic is locked. If you want to discuss this question please re-post it in the respective forum.

Does curve (x-a)^2 + (y-b)^2 = 16 intersect the Y axis?

1. a^2 + b^2 > 16
2. a = |b| + 5

Kudos [?]: 1046 [0], given: 4

CEO
Joined: 17 Nov 2007
Posts: 3584

Kudos [?]: 4580 [0], given: 360

Concentration: Entrepreneurship, Other
Schools: Chicago (Booth) - Class of 2011
GMAT 1: 750 Q50 V40

### Show Tags

28 Nov 2007, 14:05
B.

(x-a)^2 + (y-b)^2 = 16 means circle in center (a,b) and radius of 4.

1. a^2 + b^2 > 16
a=0: intersect
b=0: the circle does not intersect
INSUFF

2. a = |b| + 5 ==> a>5>4 the circle does not intersect
SUFF

Kudos [?]: 4580 [0], given: 360

CEO
Joined: 21 Jan 2007
Posts: 2734

Kudos [?]: 1046 [0], given: 4

Location: New York City

### Show Tags

28 Nov 2007, 23:37
walker wrote:
B.

(x-a)^2 + (y-b)^2 = 16 means circle in center (a,b) and radius of 4.

1. a^2 + b^2 > 16
a=0: intersect
b=0: the circle does not intersect
INSUFF

2. a = |b| + 5 ==> a>5>4 the circle does not intersect
SUFF

can you elaborate on 1? why do we set them to zero

Kudos [?]: 1046 [0], given: 4

CEO
Joined: 17 Nov 2007
Posts: 3584

Kudos [?]: 4580 [0], given: 360

Concentration: Entrepreneurship, Other
Schools: Chicago (Booth) - Class of 2011
GMAT 1: 750 Q50 V40

### Show Tags

28 Nov 2007, 23:51
bmwhype2 wrote:
can you elaborate on 1? why do we set them to zero

a=0: intersect - Distance of circle center to Y-axis is minimum - 0
b=0: the circle does not intersect - Distance of circle center to Y-axis is maximum - b

Kudos [?]: 4580 [0], given: 360

Intern
Joined: 25 Nov 2007
Posts: 38

Kudos [?]: 12 [0], given: 0

### Show Tags

29 Nov 2007, 08:15
Walker can you explain how do you know its an equation for a circle? Are there particular equations to look for so we know if they are triangles, circles, rectangles??

Kudos [?]: 12 [0], given: 0

CEO
Joined: 21 Jan 2007
Posts: 2734

Kudos [?]: 1046 [0], given: 4

Location: New York City

### Show Tags

29 Nov 2007, 15:09
shubhampandey wrote:
Walker can you explain how do you know its an equation for a circle? Are there particular equations to look for so we know if they are triangles, circles, rectangles??

http://www.analyzemath.com/CircleEq/Tutorials.html

Kudos [?]: 1046 [0], given: 4

CEO
Joined: 17 Nov 2007
Posts: 3584

Kudos [?]: 4580 [0], given: 360

Concentration: Entrepreneurship, Other
Schools: Chicago (Booth) - Class of 2011
GMAT 1: 750 Q50 V40

### Show Tags

29 Nov 2007, 15:18
Thanks, bmwhype2 for link.

we have a center of a circle - (a,b)
for any point (x,y) distance between (x,y) and the center must be constant (r -radius).

So, r^2=(x-a)^2+(y-a)^2 for any point on the circle. It is simply Pythagorean theorem.

Kudos [?]: 4580 [0], given: 360

29 Nov 2007, 15:18
Display posts from previous: Sort by

# Does curve (x-a)^2 + (y-b)^2 = 16 intersect the Y axis? 1.

 post reply Question banks Downloads My Bookmarks Reviews Important topics

 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®.