If x^2/9 - 4/y^2 = 12, what is the value of x?
(1) x/3 + 2/y = 6
(2) x/3 - 2/y = 2
Those blobs stand for negative
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i see naruto. here's my question though -
say in 1) we arbitrarily square the whole string, so we get
x^2/9 + 4/y^2 = 36
so we add the stem and this result to get
2(x^2/9) = 36
(x^2) = 2
so x = + or - 1.41
the same issue happens if you square statement 2. where did i go wrong? it doesnt say anywhere is x or y are integers or -ve.
say in 1) we arbitrarily square the whole string, so we get
x^2/9 + 4/y^2 = 36
so we add the stem and this result to get
2(x^2/9) = 36
(x^2) = 2
so x = + or - 1.41
the same issue happens if you square statement 2. where did i go wrong? it doesnt say anywhere is x or y are integers or -ve.
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niraj_a,
When you square 1) ie. (x/3 + 2/y)^2 = 6^2,
using (a+b)^2 = a^2 + 2ab + b^2
we get, (x^2/9) + 2((x/3)*(2/y)) + (4/y^2) = 36
(x^2/9) + (4x/3y) + (4/y^2) = 36
which is not equal to what you calculated.
I think this is where you might have gone wrong.
When you square 1) ie. (x/3 + 2/y)^2 = 6^2,
using (a+b)^2 = a^2 + 2ab + b^2
we get, (x^2/9) + 2((x/3)*(2/y)) + (4/y^2) = 36
(x^2/9) + (4x/3y) + (4/y^2) = 36
which is not equal to what you calculated.
I think this is where you might have gone wrong.
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Answer will be D.niraj_a wrote:If x^2/9 - 4/y^2 = 12, what is the value of x?
(1) x/3 + 2/y = 6
(2) x/3 - 2/y = 2
Those blobs stand for negative
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When i solve each of the statements , i get either y = 6 or x = 12 for both individually..vikram_k51 wrote:Answer will be D.niraj_a wrote:If x^2/9 - 4/y^2 = 12, what is the value of x?
(1) x/3 + 2/y = 6
(2) x/3 - 2/y = 2
Those blobs stand for negative
Where do i go from there in the question stem?