Answer
Foci:
$(-3,0)$ and $(3,0)$.
Work Step by Step
Major axis parallel to the x-axis, horizontal
$a^{2}=25$
$a=5$
$b^{2}=16,$
$b=4$
Center: (0,0)
Vertices: $(h-a, k),\quad (h+a, k) $
$(-5, 0),\quad (5, 0) $
Foci are $c$ units right and $c$ units left of center,
where $c^{2}=a^{2}-b^{2}:$
$c^{2}=a^{2}-b^{2}=25-16=9$
$c=3$
Foci:
$(-3,0)$ and $(3,0)$.
