Explanation: This question's it's about the function notation. Function notation is the equation 
 can be written using function notation. Consider the function represented by the equation f(x)=6x-4 and f(x) when x=8. 
First rewrite the problem down. 

Then you put by the value of x as the 8.

And then simplify and just gives us the final answer.
Don't forget to used f(x) gave us the final answer.

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