Is x = 0?
1) 3x = 2xy
2) (x^2) = x
----------
IMO [spoiler](C)[/spoiler]
1) 3x = 2xy
3x - 2xy = 0
x (3-2y) = 0
x = 0 OR 3-2y = 0
2)(x^2) = x
x = 0 OR x = 1
3)Combining 1 and 2:
x must be 0
X = 0 ?
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- MAAJ
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Woops! wrong forum, should be moved to DS Section.
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- jaymw
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It does not personally bother me that you posted this question in the "wrong" forum, because we're still talking about math stuff here:) However, please make sure that you include the source whenever you post a question. Also, it would be good to include the OA using the spoiler tag.Is x = 0?
1) 3x = 2xy
2) (x^2) = x
Now to the question:
Is x=0 ?
Statement 1: 3x=2xy
if y=1.5 then x could be any value, including zero.
Insufficient.
Statement 2: x²=x
This is true for x=0 and x=1.
Insufficient.
Combining the statements:
x=0 would make both statements correct.
x=1 could also make both statements correct, because:
3(1)=2(1)*y, is true if y=1.5
Insufficent.
[spoiler]
The answer is E.[/spoiler]
- jaymw
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That's actually not true. Although your rearrangement was correct, the conclusion drawn from it (X=0 and y = 3/2) was not. For a product to equal zero, it is ENOUGH when ONE of the factors is equal to zero. Thus, the proper conclusion is X=0 OR y = 3/2.venmic wrote:Should this answer not be A alone becuase
3x - 2xy = 0
then
x(3-2Y) = 0
then
X=0 and y = 3/2
so sufficent
how can it be C
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The solution for the equation: x(3-2Y) = 0, cannot be just x=0 AND y=3/2.venmic wrote:Should this answer not be A alone becuase
3x - 2xy = 0
then
x(3-2Y) = 0
then
X=0 and y = 3/2
so sufficent
how can it be C
It is actually, either x=0 or y=3/2 or both (x=0 and y=3/2)
- MAAJ
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This is tricky
I blindly choose C because both 1) and 2) stated x = 0
So the lesson here is that we should consider all values given by the statements and combine them?
1) x = 0 OR y = 3/2
2) x = 0 OR x = 1
3)Combined:
x = 0 AND y = 3/2
x = 1 AND y = 3/2
What's the best method to tackle this type of questions?
I blindly choose C because both 1) and 2) stated x = 0
So the lesson here is that we should consider all values given by the statements and combine them?
1) x = 0 OR y = 3/2
2) x = 0 OR x = 1
3)Combined:
x = 0 AND y = 3/2
x = 1 AND y = 3/2
What's the best method to tackle this type of questions?
"There's a difference between interest and commitment. When you're interested in doing something, you do it only when circumstance permit. When you're committed to something, you accept no excuses, only results."
- Abhishek009
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MAAJ wrote:Is x = 0?
1) 3x = 2xy
2) (x^2) = x
----------
IMO [spoiler](C)[/spoiler]
1) 3x = 2xy
3x - 2xy = 0
x (3-2y) = 0
x = 0 OR 3-2y = 0
2)(x^2) = x
x = 0 OR x = 1
3)Combining 1 and 2:
x must be 0
3x = 2xy
Can be written as
3 = 2y { Cancelling X from both sides }
Now y = 3/2
(x^2) = x
Can be written as
x = 1 { Cancelling X from both sides }
So to my knowledge none of them is sufficient to reach the conclusion x = 0.
Abhishek
- MAAJ
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Abhishek009, the second statement is a quadratic equation, so you should not solve it dividing by a variable because you could miss an answer.
x² = x
x² - x + 0 = 0
(x-1)(x-0) = 0
x = 1 OR x = 0
x = 0 is a possible solution to the equation!
x² = x
x² - x + 0 = 0
(x-1)(x-0) = 0
x = 1 OR x = 0
x = 0 is a possible solution to the equation!
Abhishek009 wrote:
3x = 2xy
Can be written as
3 = 2y { Cancelling X from both sides }
Now y = 3/2
(x^2) = x
Can be written as
x = 1 { Cancelling X from both sides }
So to my knowledge none of them is sufficient to reach the conclusion x = 0.
"There's a difference between interest and commitment. When you're interested in doing something, you do it only when circumstance permit. When you're committed to something, you accept no excuses, only results."