Find the coordinates of the focus and the vertex, the equations of the directrix and the axis, and length of the latus rectum of the parabola :

x2 = -8y


Given equation : x2 = - 8y


Comparing given equation with parabola having equation,


x2 = - 4ay


4a = 8


• a = 2


Focus : F(0,-a) = F(0,-2)


Vertex : A(0,0) = A(0,0)


Equation of the directrix : y - a=0


• y - 2=0


• y = 2


Lenth of latusrectum : 4a = 8



1