Answer
$ \quad \displaystyle \frac{x^{2}}{48}+\frac{y^{2}}{64}=1$
Work Step by Step
The center is at the midpoint of the vertices, $(0,0)$
The foci, center and vertices lie on the same line, the main axis.
Main axis here: $x=0$ (the $y$-axis).
Table 3: Major axis vertical (parallel to the y-axis)
$\begin{array}{lll}
\text{ Foci}&\text{ Vertices}&\text{ Equation}\\
{(h,k+c)}&{(h,k+a)}&{\displaystyle \frac{(x-h)^{2}}{b^{2}}+\frac{(y-k)^{2}}{a^{2}}=1}\\
{(h,k-c)}&{(h,k-a)}&{a \gt b \gt 0\text{ and }b^{2}=a^{2}-c^{2}}\end{array}$
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Vertices at $(0,\pm 8) \quad \Rightarrow \quad a=8$
Focus at $(0,-4) \quad \Rightarrow \quad c=4$
Find b:
$b^{2}=a^{2}-c^{2}=64-16=48$
$b=\sqrt{48}\approx 6.928$
The equation is $ \quad \displaystyle \frac{x^{2}}{48}+\frac{y^{2}}{64}=1$