If 5 - 6/x = x, then x has how many possible values?
(A) None
(B) One
(C) Two
(D) A finite number greater than two
(E) An infinite number
Not sure how the answer is C
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Was trying to plug in this one
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Hi shibsriz,
You'll have to do a bit of algebra to deduce the number of solutions to this equation...
5 - 6/x = x
First, multiply everything by x...
5x - 6 = x^2
Now, move everything "to the right"....
0 = x^2 - 5x + 6
You can now factor this into two terms...
0 = (x -2)(x - 3)
And answer the question...
Final Answer: C
GMAT assassins aren't born, they're made,
Rich
You'll have to do a bit of algebra to deduce the number of solutions to this equation...
5 - 6/x = x
First, multiply everything by x...
5x - 6 = x^2
Now, move everything "to the right"....
0 = x^2 - 5x + 6
You can now factor this into two terms...
0 = (x -2)(x - 3)
And answer the question...
Final Answer: C
GMAT assassins aren't born, they're made,
Rich
Last edited by [email protected] on Wed Apr 09, 2014 12:59 pm, edited 1 time in total.
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Brent@GMATPrepNow
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I just have one small point to make.
Rich's approach is great, but his factorization of x² - 5x + 6 should be (x - 2)(x - 3), rather than (x - 6)(x +1)
So, the two solutions are actually x = 2 and x = 3
Cheers,
Brent
Rich's approach is great, but his factorization of x² - 5x + 6 should be (x - 2)(x - 3), rather than (x - 6)(x +1)
So, the two solutions are actually x = 2 and x = 3
Cheers,
Brent
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Hi All,
Brent is absolutely correct - I rushed it and made a silly mistake (I've edited the original post). As it stands, my mistake doesn't actually affect the answer to this question, but it's worth noting that the details DO matter on Test Day.
GMAT assassins aren't born, they're made,
Rich
Brent is absolutely correct - I rushed it and made a silly mistake (I've edited the original post). As it stands, my mistake doesn't actually affect the answer to this question, but it's worth noting that the details DO matter on Test Day.
GMAT assassins aren't born, they're made,
Rich
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Jeff@TargetTestPrep
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We need to simplify the equation 5 - 6/x = x. We start by multiplying the entire equation by x and we obtain:[email protected] wrote:If 5 - 6/x = x, then x has how many possible values?
(A) None
(B) One
(C) Two
(D) A finite number greater than two
(E) An infinite number
5x - 6 = x^2
x^2 - 5x + 6 = 0
(x - 3)(x - 2) = 0
x = 3 or x = 2
We see that x has 2 possible values.
Answer: C
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