Respuesta :

Answer:

when f(x) = 4, the answer is 1

Step-by-step explanation:

f(x) = -2x + 9

f(4) = -2(4) + 9

= -8 + 9

= 1

Answer:

2.5

Step-by-step explanation:

-2x + 9 = 4

-2x = -5

x = 2.5