I am having a hard time understanding the difference quotient.
Ex: for f(x)= 8x+9
I understand that for every x, I put in 8x+9 for it, but what do i do for the first part where it is f(x+h)? Here is where I get confused. In some examples from school it becomes (x+h)^2 . How is that possible if you are supposed to plug in 8x+9 for every x? I dont get it.
Other problems I'm having trouble with
I'm sure with a detailed explanation, i can solve these.
Thanks for yalls help