Find and simplify each of the following for f(x) = 7x-9.(A) f(x+h)(B) f(x+h) – f(x)(C) [f(x+h)-f(x)]/h

Answer:
(a)7x+7h-9
(b)7h
(c)7
Explanation:
Given f(x) defined below:
[tex]f\mleft(x\mright)=7x-9[/tex]Part A
[tex]\begin{gathered} f\mleft(x+h\mright)=7(x+h)-9 \\ =7x+7h-9 \end{gathered}[/tex]Part B
[tex]\begin{gathered} f\mleft(x+h\mright)-f\mleft(x\mright)=\lbrack7x+7h-9\rbrack-\lbrack7x-9\rbrack \\ =7x+7h-9-7x+9 \\ =7x-7x+7h-9+9 \\ =7h \end{gathered}[/tex]Part C
Taking the result from Part B:
[tex]\begin{gathered} \frac{f\mleft(x+h\mright)-f\mleft(x\mright)}{h}=\frac{7h}{h} \\ =7 \end{gathered}[/tex]