G (f) is just a variable, and that's what confuses most people. if you wanted to, the equation could still be the same and be written as:
x = 3k (2) -22 ;k=4
But, to get the answer, you substitute k as 4, shown below:
x = 3(4) (2) -22
Next you multiply:
x = 12 (2) -22
Then multiply 12 by 2:
x = 24 -22
Then subtract and the answer will be 2
