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

 It is currently 29 May 2017, 04:43

### 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

# Challenge 25: 19

Author Message
Manager
Joined: 03 Jul 2006
Posts: 175
Followers: 1

Kudos [?]: 26 [0], given: 0

### Show Tags

13 Jul 2006, 06:49
This topic is locked. If you want to discuss this question please re-post it in the respective forum.

Q 19)

|X/2|+|Y/2|=5 encloses a region. Find its area
Intern
Joined: 11 Jul 2006
Posts: 37
Location: Boston
Followers: 0

Kudos [?]: 1 [0], given: 0

### Show Tags

13 Jul 2006, 08:47
The given equation translates to 4 equations,
Y = x + 10
Y = -x + 10
Y = x â€“ 10
Y = -x- 10

The area enclosed by these 4 lines is a square, with the X and Y intercepts being 10 on all axis. Therefore the side of the square is 10*2^(1/2). The area is this translates to 200

Cheers,
Anand
rkatl wrote:

Q 19)

|X/2|+|Y/2|=5 encloses a region. Find its area
Manager
Joined: 03 Jul 2006
Posts: 175
Followers: 1

Kudos [?]: 26 [0], given: 0

### Show Tags

13 Jul 2006, 09:29
thanks a lot.. that helps.

Can you help me with this too ?

how many roots does it have ?
sqrt(x^2+1)+sqrt(x^+2)=2

When I do it algebrically it seem have 4 roots. But the answer is 0.
Not sure if I making any mistake in assuming the no. roots for an equation
with x power 4.
Manager
Joined: 03 Jul 2006
Posts: 175
Followers: 1

Kudos [?]: 26 [0], given: 0

### Show Tags

13 Jul 2006, 09:30
btw, the explaination given for the above problem is

This equation has no roots. sqrt(x^2 + 1) is bigger than or equal to 1, sqrt(x^2 + 2) is bigger than or equal to sqrt(2). Therefore, sqrt(x^2 + 1) + sqrt(x^2 + 2) is bigger than or equal to 1 + sqrt(2), which is bigger than 2.

I can't seem to understand this logic.
Intern
Joined: 11 Jul 2006
Posts: 37
Location: Boston
Followers: 0

Kudos [?]: 1 [0], given: 0

### Show Tags

13 Jul 2006, 13:09
What I understand is you are trying to square these terms and arrive at an equation which is of the nature x^4, which leads you to believe that it has 4 roots. However, that is not always the case, any equation of the nature x^n will have n roots, but for these to be real it would have to satisfy some condition. If it does not then the roots are imaginary. That applies to the expression you get. However I am not sure what that condition is for an expression of the 4th order.
Hope this helps.
-------

rkatl wrote:
btw, the explaination given for the above problem is

This equation has no roots. sqrt(x^2 + 1) is bigger than or equal to 1, sqrt(x^2 + 2) is bigger than or equal to sqrt(2). Therefore, sqrt(x^2 + 1) + sqrt(x^2 + 2) is bigger than or equal to 1 + sqrt(2), which is bigger than 2.

I can't seem to understand this logic.
13 Jul 2006, 13:09
Display posts from previous: Sort by