The function given:
[tex]f(x)=2(x+8)[/tex]We want to find the value of x for which the functional value is 12.
We simply plug in "12" in place of "f(x)" and then solve the function algebraically.
Show below is the process:
[tex]\begin{gathered} f(x)=2(x+8) \\ 12=2(x+8) \\ 12=2x+2(8) \\ 12=2x+16 \\ 12-16=2x \\ 2x=-4 \\ x=-\frac{4}{2} \\ x=-2 \end{gathered}[/tex]Correct Answer choice is C