Which of the following is a solution to x2+y2=2x^2 + y^2 = 2x2+y2=2?
(1,1)(1, 1)(1,1)
(1,−1)(1, -1)(1,−1)
(−1,1)(-1, 1)(−1,1)
(0,0)(0, 0)(0,0)