what is the directrix and focus of the equation 1/16(y+4)^2=x-3

Answer 1

The parabola y = 1/4d x^2 has

vertex at (0,0)
focal distance = d
focus at (0,1)
directrix y = -1

Now we have transformed our equation to

(x-3) = 1/4*4 (y+4)^2
with
vertex at (3,-4)
focal distance = 4
focus at (7,-4)
directrix x = -1