If f(x) = 3x – 2, find f(-5).
Note
Substitute x = -5 into the function: f(-5) = 3 × -5 - 2 = -17. A function gives an output for each input. To evaluate f(x), replace every x in the rule with the given number before simplifying. Be especially careful with negative inputs, because multiplying two negative signs can make a positive result. The correct answer is -17, which matches the calculation or reasoning shown.
