Question

how to find the focus and directrix for the parabola y=(x/4)^2 (squared)

Answer 1

Change it into standard form:
\[x^2 = 4ay\]
\[y = x^2/16 \]
\[x^2=16y\]

Find a:
4a=16
a=4

And then you find the vertex, which is (0,0)
From there you can deduce that the focus will be (0,4)
Directrix is y=-4

Answer 2

good