Which of these represents a parabola with vertex (0,0)(0,0)(0,0) and focus (0,−3)(0, -3)(0,−3)?
x2=−12yx^2 = -12yx2=−12y
y2=−12xy^2 = -12xy2=−12x
x2=12yx^2 = 12yx2=12y
y2=12xy^2 = 12xy2=12x