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[email protected]
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x = sqrt ( 4y(x-y) )
Go check x with the answer. Plug it in the equation, it will be A
Please explain- Equation
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Source: Beat The GMAT — Quantitative Reasoning |
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dominhtri1995
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you will have
x = sqrt ( 4y(x-y) )
Go check x with the answer. Plug it in the equation, it will be A
x = sqrt ( 4y(x-y) )
Go check x with the answer. Plug it in the equation, it will be A
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[email protected]
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Hi shibsriz,
This question has a hidden Classic Quadratic within it.
Start by squaring both sides of the equation:
X^2 = 4XY -4Y^2
Notice how there's a "squared" X term and a "squared" Y term? That's the big clue that you're looking at a quadratic.
X^2 - 4XY + 4Y^2 = 0
Now factor:
(X - 2Y)^2 = 0
X = 2Y
Final Answer: A
GMAT assassins aren't born, they're made,
Rich
This question has a hidden Classic Quadratic within it.
Start by squaring both sides of the equation:
X^2 = 4XY -4Y^2
Notice how there's a "squared" X term and a "squared" Y term? That's the big clue that you're looking at a quadratic.
X^2 - 4XY + 4Y^2 = 0
Now factor:
(X - 2Y)^2 = 0
X = 2Y
Final Answer: A
GMAT assassins aren't born, they're made,
Rich
GMAT/MBA Expert
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Mike@Magoosh
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Dear [email protected],
It appears that Rich gave you a good solution to this particular problem.
I would just like to recommend knowing cold three fundamental algebra equations:
https://magoosh.com/gmat/2013/three-alge ... -the-gmat/
These are shortcuts that will help you a lot.
Mike
It appears that Rich gave you a good solution to this particular problem.
I would just like to recommend knowing cold three fundamental algebra equations:
https://magoosh.com/gmat/2013/three-alge ... -the-gmat/
These are shortcuts that will help you a lot.
Mike
Magoosh GMAT Instructor
https://gmat.magoosh.com/
https://gmat.magoosh.com/
