You have to me more specific with this question
I don't fully understand the question.
Given the function below:

To find f(-2), we substitute x = -2 in the equation. Since f(-2) means the value of f(x) at x = -2.

Replace x-term to -2 and evaluate.

Answer
Let me know if you have any doubts!
Answer:
9/4 OR 2 1/4
Step-by-step explanation:
-3/2 to the second power is -3/2 * -3/2 so you multiply the numerators together and you multiply the denominators together then put it back as a fraction
-3 *-3 = 9
2 *2 =4
9/4 or in mixed form 2 1/4
Mathematical equation -
20 + 0.50x = ?
X is the placeholder which in this case equals months
But in this case you want to look for form month three to month 18 (which is 15 months) so three months went by so the equation is
$61.50(being the three months already)
(20+(0.50*15))+61.50=?