Answer:
[tex]2x^{2} -4x - 16[/tex]
Step-by-step explanation:
[tex](2x+4)(x-4)\\= (2x)(x) + (2x)(-4) + 4(x) + (4)(-4)\\= 2x^{2} - 8x + 4x - 16\\= 2x^{2} - 4x-16[/tex]
First, we use the distributive rule to get rid of the parenthesis. Then, we combine like terms and get out final answer!