Stmt 2)
2x + 5y = 20
y = (20 - 2x)/5
We know that -2x > 3y
-2x > (60 - 6x) / 5
-10x > 60 - 6x
-4x > 60
x < -15 (remember, sign changes when you multiply or divide by a negative number)
If x < -15, it must be negative.
Thus, sufficient to answer the question
If -2x > 3y ,is x negative ?
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GMATGuruNY
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If -2x > 3y, then x<0 when y>0. Thus, we can rephrase the question as:himanshi wrote:Hi,
I tried to search this question but couldn't find any link.
Q . If -2x > 3y ,is x negative ?
1) y > 0
2) 2x + 5y -20 =0
The AO is : D
But I marked A. I don't understand why 2) is sufficient alone... ?
Thanks
Is y>0?
Statement 1:
Tell us that y>0. Sufficient.
Statement 2:
2x+5y-20 = 0.
5y-20 = -2x.
Substituting 5y-20 for -2x in -2x>3y, we get:
5y-20>3y
2y>20
y>10. Sufficient.
The correct answer is D.
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kmittal82
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If y=0, then -2x > 0gdk800 wrote:Hi,
I might be going a bit off topic, but what if Y = 0 in this case? How do you justify the answers?
I will be glad if you can clear this doubt.
Thanks
x < 0, so the question stem itself is enough to answer the question.
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goyalsau
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I think Important thing to learn over here is that equation with alligators { < , > } are as important as equal to { = }himanshi wrote: Q . If -2x > 3y ,is x negative ?
1) y > 0
2) 2x + 5y -20 =0
I always had the perception that only equation with equal to { = } form a equation, but here in this problem we can see that -2x > 3y Helped us in finding a specific value,
Or i must we generally don't get the specific value , We can find the range in which the answer will lie,
example if x < -1 , { Now we know that x will always be -ve } This may not be very Helpful in problem solving questions But in DS questions, It is as important a information as x = 2 ,
I know, This is a general thing but i thought its good i to rewind because i was not able to figure out why answer is D.
Saurabh Goyal
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