What is the value of expression (2(x+y)^2) / (2(x-y)^2)

[amollate]

Hi,

The following is the GMAT Prep problem.

If xy = 1, What is the value of (2(x+y)^2) / (2(x-y)^2)

A. 2
B. 4
C. 8
D. 16
E. 32

The answer is D. Can you please explain the solution?

[RonPurewal]

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