I need help with this. Can somebody please explain?
What is the value of x, if x^2 - y^2 = 0
(1) X>= 5
(2) y = -3
I thought the answer is C. When I looked the answer, it was E.
I did this:
(1) Alone is insufficient because it provides no information about Y
(2) Alone is insufficient because it provides no information about X
Together X greater than or equal to 5
So, let's take x = 5
y = - 3
(x+y)(x-y)> 0 ?
(5 - 3) (5 + 3) > 0 ?
Yes.
Therefore, C is the answer.
However, answer is E.
Can somebody tell me where I went wrong?
Thanks!
Data Sufficiency Question
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Can you repost the original question? Is the question looking for 'x' or for whether or not it's greater than zero? Your notes make that unclear.sparkles3144 wrote:I need help with this. Can somebody please explain?
What is the value of x, if x^2 - y^2 = 0
(1) X>= 5
(2) y = -3
I thought the answer is C. When I looked the answer, it was E.
I did this:
(1) Alone is insufficient because it provides no information about Y
(2) Alone is insufficient because it provides no information about X
Together X greater than or equal to 5
So, let's take x = 5
y = - 3
(x+y)(x-y)> 0 ?
(5 - 3) (5 + 3) > 0 ?
Yes.
Therefore, C is the answer.
However, answer is E.
Can somebody tell me where I went wrong?
Thanks!
Thanks.
Brian
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Instructor, Manhattan GMAT
Expert Contributor to Beat The GMAT
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Brian Lange
Instructor, Manhattan GMAT
Expert Contributor to Beat The GMAT
Merci, Danke, Grazie, Gracias -- Whichever way you say it, if you found my post helpful, please click on the 'thank' icon in the top right corner of this post.
And I encourage you to click on 'follow' to track all my posts -- all the cool kids are doing it!
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Are you sure you transcribed the question correctly?sparkles3144 wrote:I need help with this. Can somebody please explain?
What is the value of x, if x^2 - y^2 = 0
(1) X>= 5
(2) y = -3
I thought the answer is C. When I looked the answer, it was E.
I did this:
(1) Alone is insufficient because it provides no information about Y
(2) Alone is insufficient because it provides no information about X
Together X greater than or equal to 5
So, let's take x = 5
y = - 3
(x+y)(x-y)> 0 ?
(5 - 3) (5 + 3) > 0 ?
Yes.
Therefore, C is the answer.
However, answer is E.
Can somebody tell me where I went wrong?
Thanks!
If x > 5 and y = -3, then it's impossible for x^2 - y^2 to equal 0
Cheers,
Brent
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- Master | Next Rank: 500 Posts
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- Joined: Fri Jan 18, 2013 8:27 am
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Hello,
I am sorry. I made a typo.
It is
What is the value of x, if x^2 - y^2 > 0 ?
(1) x>=5
(2) y = -3
Thanks!
I am sorry. I made a typo.
It is
What is the value of x, if x^2 - y^2 > 0 ?
(1) x>=5
(2) y = -3
Thanks!
GMAT/MBA Expert
- Brent@GMATPrepNow
- GMAT Instructor
- Posts: 16207
- Joined: Mon Dec 08, 2008 6:26 pm
- Location: Vancouver, BC
- Thanked: 5254 times
- Followed by:1268 members
- GMAT Score:770
Target question: What is the value of x?sparkles3144 wrote: What is the value of x, if x^2 - y^2 > 0 ?
(1) x>=5
(2) y = -3
Thanks!
Given: x^2 - y^2 > 0
Statement 1: x > 5
x can have several values.
Since we cannot answer the target question with certainty, statement 1 is NOT SUFFICIENT
Statement 2: y = -3
x can have several values.
Since we cannot answer the target question with certainty, statement 2 is NOT SUFFICIENT
Statements 1 and 2 combined:
There are several pair of values that satisfy both conditions. Here are two:
Case a: x = 5 and y = -3
Case b: x = 6 and y = -3
Since we still cannot answer the target question with certainty, the combined statements are NOT SUFFICIENT
Answer = E
Cheers,