The vertex of the parabola y2−4y−x+4=0y^2 - 4y - x + 4 = 0y2−4y−x+4=0 is:
(0,2)(0, 2)(0,2)
(0,0)(0, 0)(0,0)
(2,0)(2, 0)(2,0)
(4,2)(4, 2)(4,2)