f(x) = 8x-9
f(4)
let x=4 and substitute in
f(4) = 8*4 -9
f(4) = 32-9
f(4) = 23
Given [tex]f(x)=8x-9[/tex], they want you to find [tex]f(4).[/tex]
This is basically evaluating a function. Simply put 4 into x of the function.
Hence,
[tex]f(4)=8(4)-9=23[/tex]
ANSWER: 23
