If x and y are non-zero integers, and 49x^4 – 4y^4 = 7x^2 + 2y^2, which of the following could be the value of x2 in terms of y?  Pick:
A) 2y^2	B) 2y^2+1/7	C) 2y^4	D) 2y^2-1/7	E) 2y^2+1/8
49x^4 – 4y^4 = 7x^2 + 2y^2   (7x^2 + 2y^2) (7x^2 - 2y^2) = 7x^2 + 2y^2   7x^2 - 2y^2 = 1   7x^2 = 2y^2+1   x^2 = 2y^2+1/7   Answer : 2y^2+1/7
<result>B</result>
If x and y are non-zero integers, and 49x^4 – 4y^4 = 7x^2 + 2y^2, which of the following could be the value of x2 in terms of y?