Respuesta :

Answer:

f(-9) = -23

Step-by-step explanation:

Step 1:  Identify the function

f(x) = 3x + 4

Step 2:  Set x to -9 in the function

f(-9) = 3(-9) + 4

Step 3:  Multiply

f(-9) = -27 + 4

Step 4:  Add

f(-9) = -23

Answer:  f(-9) = -23