Answer:
D
Step-by-step explanation:
You have to be careful that you treat 21 as special. It is the only positive number. As you do the problem, keep an eye on 21.
f(-2) = 3x^2 - 2x + 5 Put -2 wherever you see an x
f(-2) = 3(-2)^2 - 2(-2) + 5 Calculate the first term.
f(-2) = 3(4) - 2(-2) + 5 Remove the brackets of the second term
f(-2) = 12 + 4 + 5 Combine
f(-2) = 21
