The line y=0y = 0y=0 is a tangent to x2+y2=9x^2 + y^2 = 9x2+y2=9 at which point?
(3,0)(3, 0)(3,0)
(0,3)(0, 3)(0,3)
It is not a tangent
(0,0)(0, 0)(0,0)