Which of these is a solution to x2−2y2=7x^2 - 2y^2 = 7x2−2y2=7?
(3,1)(3, 1)(3,1)
(5,3)(5, 3)(5,3)
(9,6)(9, 6)(9,6)
(3,−1)(3, -1)(3,−1)