Question 1086598
You need to just make the appropriate substitutions and then simplify the difference quotient expression.


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NOT both f and F as 5x-4.  Choose either of them and stick to it.


{{{f(x)=5x-4}}},  your given function


{{{f(x+h)=5(x+h)-4}}},  using {{{x+h}}} as the function's input


h, the increment to have been made to x


DO THE SUBSTITUTIONS INTO DIFFERENCE QUOTIENT:
{{{(5(x+h)-4-(5x-4))/h}}}
AND SIMPLIFY THIS EXPRESSION!





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