Which of the following points is the center of the hyperbola x2−4y2+6x+8y−11=0x^2 - 4y^2 + 6x + 8y - 11 = 0x2−4y2+6x+8y−11=0?
(3,1)(3, 1)(3,1)
(−3,1)(-3, 1)(−3,1)
(−3,−1)(-3, -1)(−3,−1)
(3,−1)(3, -1)(3,−1)