F irst
O uters
I nners
L ast
We first need to expand the equation By finding what adds up to 16 and multiples to 48
X^2 + 16x + 48 = x^2 + 12x + 4x + 48.
According to the foil method
(a + b)(c + d) = ac + ad + bc + bd
ac = x^2
ad = 12x
bc = 4x
bd = 48.