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If y + y = 0, which of the following [#permalink]
03 Jun 2018, 07:20
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If y + y = 0, which of the following must be true? A. y > 0 B. Y ≥ 0 C. Y < 0 D. Y ≤ 0 E. Y = 0 src: Orbit Test Prep




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Re: If y + y = 0, which of the following [#permalink]
07 Jun 2018, 23:25
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amorphous wrote: If y + y = 0, which of the following must be true?
A. y > 0
B. Y ≥ 0
C. Y < 0
D. Y ≤ 0
E. Y = 0
src: Orbit Test Prep Please share answer explanation.



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Re: If y + y = 0, which of the following [#permalink]
08 Jun 2018, 02:03
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From the given eqn take y to the left side of the eqn we get, y =  yHence, y = y; only 0 satisfies the conditionor, y = y or y = y; Any no would satisfy the condition.Only 0 satisfies both the condition hence, 0
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Re: If y + y = 0, which of the following [#permalink]
08 Jun 2018, 04:04
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x is always positive. Please note some absolute value properties:
1. When x ≤ 0 ,then x = −x . For example: −10= (10) = 10
2. When x ≥ 0 ,then x=x , For example 10 = 10
So,in our question we are given y+y=0 > y = y . This implies that y ≤ 0. This is similar to first property.
Hence, answer must be D.



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Re: If y + y = 0, which of the following [#permalink]
09 Jun 2018, 10:52
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PankajPatel wrote: x is always positive. Please note some absolute value properties:
1. When x ≤ 0 ,then x = −x . For example: −10= (10) = 10
2. When x ≥ 0 ,then x=x , For example 10 = 10
So,in our question we are given y+y=0 > y = y . This implies that y ≤ 0. This is similar to first property.
Hence, answer must be D. Exactly Pankaj...when I saw the options I got doubt and I was not happy with answer explanation , but I must appreciate amorphous effort. We are given that y + y = 0. Now y = y .. note here y is always positive now in order to LHS and RHS have to be postive , RHS i.e. y to be +ve , y values has to be ve. then y = (Y)... then it'll be correct. Here y has to be < 0 . Note : 0 is neither +ve or ve but only even number. In that case only C can be correct. But as per absolute principle, D comes. I want Experts to validate my explanation.



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Re: If y + y = 0, which of the following [#permalink]
09 Jun 2018, 11:08
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for y + y = 0 y itself must be zero. This is a must true question. From A to D any value does not make the sum = 0 regardless if you do know that y is always positive. That fact is a bit redundant to a clever student.
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Re: If y + y = 0, which of the following [#permalink]
10 Jun 2018, 09:57
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Yes msk0657. It is a MUST BE TRUE question so considering CAN BE TRUE is a trap answer while solving these type of questions.



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Re: If y + y = 0, which of the following [#permalink]
03 May 2019, 19:31
So, as the question is asking for a MUST be true ( NOT a can be true), is the answer E Correct? pls, need undisputed solution .



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Re: If y + y = 0, which of the following [#permalink]
03 May 2019, 20:52
jelal123 wrote: So, as the question is asking for a MUST be true ( NOT a can be true), is the answer E Correct? pls, need undisputed solution . Answer is D as per gmatclub. Bunuel just nailed it Reference: https://gmatclub.com/forum/ifyy0whi ... 31099.html



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Re: If y + y = 0, which of the following [#permalink]
04 May 2019, 00:02
\(y + y = 0\) We do have two case scenarios 1) if two numbers are added and the result is zero AND considering that y must be positive always OR the other y is negative and the same of \(y\) or \(y\) itself is zero. Therefore y must be \(\leq 0\) 2) \(y = y \) In this case y is positive and to cancel out y must be < 0 Or \(y = 0\) Therefore \(y \leq 0\) 1) + 2) \(y \leq 0\)
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Re: If y + y = 0, which of the following [#permalink]
04 May 2019, 07:31
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amorphous wrote: If y + y = 0, which of the following must be true?
A. y > 0 B. y ≥ 0 C. y < 0 D. y ≤ 0 E. y = 0
The question asks "What must be true?" So, if an answer choice is not necessarily true, we can ELIMINATE it. Find a solution to the equation y + y = 0 One possible solution is y = 1, since 1 +  1 = 0 Now check the answer choices.... A. 1 > 0. Not true. ELIMINATE B. 1 ≥ 0. Not true. ELIMINATE C. 1 < 0. True. KEEP D. 1 ≤ 0. True. KEEP E. 1 = 0. Not true. ELIMINATE B and C are the REMAINING answer choices. Now find another solution to the equation y + y = 0 Another possible solution is y = 0, since 0 +  0 = 0 Now check the REMAINING answer choices.... C. 0 < 0. Not true. ELIMINATE D. 0 ≤ 0. True. KEEP By the process of elimination (POE), the correct answer is D Cheers, Brent
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Re: If y + y = 0, which of the following
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