Calculate: (2x+4)(x-4)

Expression: $(2x+4)(x-4)$

Apply FOIL method $\left(a+b\right)\left(c+d\right)=ac+ad+bc+bd$

$=2xx+2x(-4)+4x+4(-4)$

Simplify $2xx+2x(-4)+4x+4(-4):{\quad}2x^{2}-4x-16$

$=2x^{2}-4x-16$