
Marc D. answered 12/01/20
Engaging and patient Master of Applied Mathematics.
if the equation is of the form y = a(x-h)2 + k then given
y = 1/16 * (x-2)2 -1
k = -1, h = 2 and a = 1/16 and from a prior question the focus is (2,3).
This gives that the axis of symmetry is the line x = 2. You can see this by noticing that the focus is always above the vertex of the parabola or in other words, it shares the x-coordinate with the vertex.
The axis of symmetry will run parallel with the y-axis and at right angles to the x-axis.