Answer:
[tex]x^{2} - 16\\[/tex]
Step-by-step explanation:
FOIL stands for first, outer, inner, last. That means we multiply sets of terms together in that order.
(x+4)(x-4)
first: [tex]x^{2}[/tex]
(x+4)(x-4)
outer: -4x
(x+4)(x-4)
inner: 4x
(x+4)(x-4)
last: -16
Add these all together.
x^2 - 4x + 4x - 16
Simplify the middle terms.
[tex]x^{2} - 16\\[/tex]