Find the directrix of the parabola whose equation is y= x^2/32
x=-8
x=8
y=-8

Y= -8 because parabola never intersects your directrix. So, your directrix (red line) is this: (see first photo with graph) and your formula has to be this (since the directrix never intersect the parabola meaning the parabola has to go down) here’s a photo explaining which formula you use AND it tells what your directrix would look like when using these formulas and which value it is (meaning X or Y)! - see second photo!