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If xy ≠ 0, is x = y? (1) x = y (2) xy > 0
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27 Mar 2018, 02:30
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73% (00:31) correct 27% (00:40) wrong based on 97 sessions
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If xy ≠ 0, is x = y? (1) x = y (2) xy > 0 Statement (1) is not sufficient as x could be either >0 or <0 and same for y
Statement (2) is also insufficient as if x>0 then y must be >0 to have xy>0 and if x<0 then y must be <0 to have xy>0 but x could differ from y
However, I do not understand why taking together statement (1) and statement (2) is sufficient as we have two possibilities: x>0 y>0 , lxl=lyl , then x=y x<0 y<0, lxl=lyl, then x=y
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Re: If xy ≠ 0, is x = y? (1) x = y (2) xy > 0
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27 Mar 2018, 06:06
HIUY wrote: If xy ≠ 0, is x = y? (1) x = y (2) xy > 0 Statement (1) is not sufficient as x could be either >0 or <0 and same for y
Statement (2) is also insufficient as if x>0 then y must be >0 to have xy>0 and if x<0 then y must be <0 to have xy>0 but x could differ from y
However, I do not understand why taking together statement (1) and statement (2) is sufficient as we have two possibilities: x>0 y>0 , lxl=lyl , then x=y x<0 y<0, lxl=lyl, then x=y If xy ≠ 0, is x = y?(1) x = y. This implies that x and y are same distance from 0: either x = y or x = y. Not sufficient. (2) xy > 0. This implies that x and y have the same sign. Not sufficient. (1)+(2) Since from (2) we know that x and y have the same sign and from (1) we know that x and y are same distance from 0, then it must be true that x = y. Sufficient. Answer: C. HIUY wrote: If xy ≠ 0, is x = y?
(1) x = y (2) xy > 0
Statement (1) is not sufficient as x could be either >0 or <0 and same for y
Statement (2) is also insufficient as if x>0 then y must be >0 to have xy>0 and if x<0 then y must be <0 to have xy>0 but x could differ from y
However, I do not understand why taking together statement (1) and statement (2) is sufficient as we have two possibilities: x>0 y>0 , lxl=lyl , then x=y x<0 y<0, lxl=lyl, then x=y Are both cases you have there the same? The question asks whether x = y and both cases give an YES answer to the question.
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Re: If xy ≠ 0, is x = y? (1) x = y (2) xy > 0
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27 Mar 2018, 13:43
HIUY wrote: If xy ≠ 0, is x = y? (1) x = y (2) xy > 0 Statement (1) is not sufficient as x could be either >0 or <0 and same for y
Statement (2) is also insufficient as if x>0 then y must be >0 to have xy>0 and if x<0 then y must be <0 to have xy>0 but x could differ from y
However, I do not understand why taking together statement (1) and statement (2) is sufficient as we have two possibilities: x>0 y>0 , lxl=lyl , then x=y x<0 y<0, lxl=lyl, then x=y Straight C. 1 We do not know anything about their sign. X can be +5 and Y can be 5. Not sufficient. 2 X and Y can be any number other than 0. This statement does tell us that both x and y have the same sign. Statement 1 and 2 together are sufficient. Hence C.
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Re: If xy ≠ 0, is x = y? (1) x = y (2) xy > 0
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30 Mar 2018, 08:44



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Re: If xy ≠ 0, is x = y? (1) x = y (2) xy > 0
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30 Mar 2018, 09:02
HIUY wrote: If xy ≠ 0, is x = y?
(1) x = y (2) xy > 0 Statement 1: It tells you only that distance of x and y from 0 on the number line equal. Insufficient Statement 2: It tells you only that sign of x and y are same. Insufficient Combining we know that x = y (C)
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Re: If xy ≠ 0, is x = y? (1) x = y (2) xy > 0 &nbs
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30 Mar 2018, 09:02






