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Put this in your calculator and shmoop it...

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2 xy + 2 = 1 over x + y.

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Solve for y in terms of x.

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And here are the potential answers...

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It's important to remember that when a question asks us to solve for something in terms of

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something else, it's just asking us to isolate the variable.

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So let's get started. We need to isolate y.

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We can do this by putting all the terms with y's on one side first.

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We subtract y from both sides, and 2 from both sides.

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Next, we'll factor out the y on the left side of the equation, and we're left with y times

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the quantity 2x - 1 is equal to 1/x - 2.

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Then, we divide both sides by 2x - 1, so our y is isolated.

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We can factor out 1/x from the top half of the right side,

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and we'll be left with (1/x)(1 - 2x) on top.

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Now, the top has 1 - 2x, and the bottom has 2x - 1.

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Well look at them closely...they're just negatives of each other.

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So, we can rewrite the bottom as -1 times 1 - 2x

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We can clearly see that 1 - 2x can be cancelled out.

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We're left with y = -1/x.

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So our answer is (A).

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