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If x/y = 1 which of the following must be true?
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17 Jul 2016, 09:36
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If x/y = 1 which of the following must be true? A) x = y B) x = y C) x = y^2 D) x^2 = y^2 E) x^3 = y^3
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If x/y = 1 which of the following must be true?
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17 Jul 2016, 09:43
Avigano wrote: If x/y = 1 which of the following must be true?
A) x = y B) x = y C) x = y^2 D) x^2 = y^2 E) x^3 = y^3 x/y = 1 y = x, this implies that x is 0 or negative. Square: y^2 = x^2. Answer: D. Alternatively you can try number plugging: try x = 2 and y = 2 or 2. You'll see that only D is always true.
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Re: If x/y = 1 which of the following must be true?
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17 Jul 2016, 09:56
Avigano wrote: If x/y = 1 which of the following must be true?
A) x = y B) x = y C) x = y^2 D) x^2 = y^2 E) x^3 = y^3 Hi! There, x/y = 1 x= 1 y Squaring both sides x^2= (1 y) ^2= y^2 D is the answer Squaring any ve number yields +ve number. Let's see why other options are not right A) x = y What if x= 2 and y= 2. This does'nt hold good then.B) x = y If x=2 and y=2. This is not right.C) x = y^2 This means x is +ve and y is always +ve. In this case x/y can not be ve. not correct.D) x^2 = y^2. Explained above.E) x^3 = y^3. If x= 2 and y= 2. This will not hold true.D is the answer
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Re: If x/y = 1 which of the following must be true?
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17 Jul 2016, 09:50
Thank you Bunuel, clearer than spring water.



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Re: If (x/y)=1,Which of the following must be true ?
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26 Jul 2016, 06:47
NandishSS wrote: If (x/y)=1,Which of the following must be true ? A) x = —y B) x = y C) x=y^2 D) x^2 = y^2 E) x^3 = y^3 Quick way to solve? Given (x/y)=1 Then we can take two cases and the options must satisfy both cases. 1. x/y = 1 2. x/y = 1 Option A : sub x = y in two cases then in one case satisfies and the other doesn't B) x = y : sub x = y in two cases , then in one case satisfies and the other doesn't C) x=y^2 : sub x = y^2 in two cases then in one case satisfies and the other doesn't D) x^2 = y^2 => x = √y^2 = y in both case we get the same result. ( in one case assume +ve and other case ve)> Correct option.E) x^3 = y^3 => x = y => sub x = y in two cases , then in one case satisfies and the other doesn't...



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Re: If (x/y)=1,Which of the following must be true ?
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26 Jul 2016, 06:56
NandishSS wrote: If (x/y)=1,Which of the following must be true ? A) x = —y B) x = y C) x=y^2 D) x^2 = y^2 E) x^3 = y^3 Quick way to solve? Attachment:
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Re: If x/y = 1 which of the following must be true?
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07 Sep 2016, 16:28
mjhoon1004 wrote: Hello Gmatclubbers,
I stumbled upon this question on one of the Prep packs and am having a trouble understanding it. I'd appreciate if any of you can help explain. Thanks. Hi, If x/y=1.... Two things can be made out... X must be numerically similar to y, may not be the sign... X must be NEGATIVE.... We do not know whether y is +or...... So if we say x=y and y is , x will become +, and ans will be 1... Only x^2=y^2 will be true irrespective of SIGN....
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Re: If x/y = 1 which of the following must be true?
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07 Sep 2016, 16:32
mjhoon1004 wrote: Hello Gmatclubbers,
I stumbled upon this question on one of the Prep packs and am having a trouble understanding it. I'd appreciate if any of you can help explain. Thanks. x / y = 1 y can be +ve or ve case 1 : y is +ve x/y = 1 implies x = y case 2 : y is ve x/y = 1 implies x = y from 1 and 2 we can always say x2 = y2 i would go with D whats OA?



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Re: If x/y = 1 which of the following must be true?
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07 Sep 2016, 17:52
Since absolute value is always >= 0, we can safely square it.
x / y = 1
Square both sides.
x^2 / y^2 = 1 x^2 = y^2
This must be true.
Answer (D).



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Re: If x/y = 1 which of the following must be true?
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07 Sep 2016, 19:20
Hi mjhoon1004, This question can be solved by TESTing VALUES. We're told that X/Y = 1. We're asked which of the following MUST be true (meaning "which is ALWAYS TRUE no matter how many different examples you come up with??"). IF.... X = 2 Y = 2 Then we can eliminate Answers B, C and E IF... X = 2 Y = 2 Then we can eliminate Answer A Final Answer: GMAT assassins aren't born, they're made, Rich
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If x/y=1, which of the following must be true?
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21 Nov 2016, 13:10
If \(\frac{x}{y}=1\), which of the following must be true?
A)\(x=y\) B)\(x=y\) C) \(x=y^2\) D) \(x^2=y^2\) E) \(x^3=y^3\)



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Re: If x/y=1, which of the following must be true?
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21 Nov 2016, 18:31
felippemed wrote: If \(\frac{x}{y}=1\), which of the following must be true?
A)\(x=y\) B)\(x=y\) C) \(x=y^2\) D) \(x^2=y^2\) E) \(x^3=y^3\) Hi \(\frac{x}{y}=1\) means the NUMERIC value of x and y has to be same , sign may not be.. The second point is that since y will be positive, x will be NEGATIVE.. Now two cases 1) x = y... x=y=3.. So \(\frac{3}{3}=\frac{3}{3}=1\) 2) x=y.. X=3, y=3... \(\frac{2}{3}=1\).. ONLY an EVEN power can make two values equal in both cases So D is answer.. Also choices give away answer.. Say A is the answer then D also must be true.. but can we have two answers..NO If B is the answer, then D and E also must be true.. This way you can home on to D
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Re: If x/y=1, which of the following must be true?
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21 Nov 2016, 19:25
felippemed wrote: If \(\frac{x}{y}=1\), which of the following must be true?
A)\(x=y\) B)\(x=y\) C) \(x=y^2\) D) \(x^2=y^2\) E) \(x^3=y^3\) \(\frac{x}{y}=1 \implies x=y \implies x^2 = y^2\) The answer is D C is out. \(x=y \implies x=y\) if y<0 or \(x=y\) if y>0. A, B is out. \(x=y \implies x^3=y^3 \implies x^3=y^3\) if y<0 or \(x^3=y^3\) if y>0. E is out
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Re: If x/y = 1 which of the following must be true?
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30 Nov 2016, 07:22
x/sqrt (y^2)=1 x=sqrt(y^2) Squaring both side X^2=y^2 D Sent from my SAMSUNGSMG935A using GMAT Club Forum mobile app



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If x/y = 1 which of the following must be true?
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02 Dec 2016, 04:24
Here is my theoretical approach to the problem. A real good one to solidify concepts Posted from my mobile device TIP: If you are still struggling with the objective of the question, look at the equations as sausagemaker machines. The goal is to produce similar products despite the ingredients (but the amount of them must be equal). In other words, if I plug in signals within them, the output MUST be equal.
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Re: If x/y = 1 which of the following must be true?
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25 Jan 2017, 03:28
Why would we square a modulus??? Omg I dont understand ANYTHING if this...



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Re: If x/y = 1 which of the following must be true?
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16 May 2017, 04:09
If x/y = 1 which of the following must be true?
A) x = y B) x = y C) x = y^2 D) x^2 = y^2 E) x^3 = y^3
my 2 cents.
x=y this means x=y or x=(y) So, A) and B) are out. C), doens't make sense. D), if we square both then signs in front of a variable does not matter so this is good. E), if we cute, then negative signs remain, so out.
Hence D.



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Re: If x/y = 1 which of the following must be true?
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14 Feb 2018, 23:39
TEST IT: to get 1, X could be 1, then y could be 1 or 1.
a) 1 =  (1) but not (1) > OUT b) 1 = 1 but not 1 > OUT c) 1 not equal to (1)^2 nor (1)^2 > OUT d) (1)^2 = (1)^2 and (1)^2 > CORRECT e) (1)^3 = (1)^3 but not (1)^3 > OUT



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Re: If x/y = 1 which of the following must be true?
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26 Mar 2019, 06:14
Bunuel wrote: Avigano wrote: If x/y = 1 which of the following must be true?
A) x = y B) x = y C) x = y^2 D) x^2 = y^2 E) x^3 = y^3 x/y = 1 y = x, this implies that x is 0 or negative. Square: y^2 = x^2. Answer: D. Alternatively you can try number plugging: try x = 2 and y = 2 or 2. You'll see that only D is always true. Absolute value cannot equal negative number. Shouldn't the representation be x=y instead of y=x?



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Re: If x/y = 1 which of the following must be true?
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16 Dec 2019, 11:07
Divyadisha  I have a question. My understanding was that you can square both sides in an equation when both sides are positive. Is that true or am I not looking at this question right?




Re: If x/y = 1 which of the following must be true?
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