Find the coordinates of the focus, axis of the parabola, the equation of the directrix and the length of the latus rectum. x² = -9y

The given equation involves x², so the axis of symmetry is y-axis.

x² = -4 ⇒ -4ay

where a = > 0

The coefficient of y is negative. The parabola opens downwards.

Focus = , equation of directrix y = , the length of latus rectum

        = 4a = 4 × = 9 and the equation of axis is x = 0.