Equation of parabola : y^{2} = -16x

On comparing with : y^{2} = -4ax , 4a = 16 , a = 4

Focus : S = (-a,0) = (-4,0)

Equation of directrix :

x - a = 0

**∴** x - 4 = 0

Length of latus recturm = 4a = 16 units

Ends of latus rectum :

L = (a , 2a) = (-4,8)

L’= (-a,-2a) = (-4,-8)