SAT Math Question of the Day

Q: If f(x) = x² - 3, then f(a) =

1. a² - 3
2. 2a - 3
3. x² - 3
4. 2x - 3
5. ax² - 3

UNANSWERED.

The correct answer is A.

A: The correct answer is a² - 3.

Substitute a wherever the x occurs in the equation:
f(x) = x² - 3
f(a) = a² - 3