Thanks for your questions. Your questions is
If f(x) = 4(x + 2), then what will be the value of f(3)?

Correct answer is: a

Questions details Explanation:
According to the data given in the question, f(x) = 4(x + 2)
We have to find out the value of f(3).
∴ Substituting, x=3 in the equation for f(x), we get,
f(3) = 4(3 + 2)
∴ f(3) = 4(5) = 20
Hence, f(3) = 20
Hence, the correct answer is option a.

Hope you are now clear. Ask your questions for more help.