find the difference quotient of f; that is, find $\frac{f(x + h)-f(x)}{h}$, h ≠ 0, for the following…

find the difference quotient of f; that is, find $\frac{f(x + h)-f(x)}{h}$, h ≠ 0, for the following function. be sure to simplify.\nf(x)=x² - 9x + 5\n$\frac{f(x + h)-f(x)}{h}=square$ (simplify your answer.)
Answer
Explanation:
Step1: Find f(x + h)
Substitute x + h into f(x): [ \begin{align*} f(x + h)&=(x + h)^2-9(x + h)+5\ &=x^{2}+2xh+h^{2}-9x - 9h+5 \end{align*} ]
Step2: Calculate f(x + h)-f(x)
[ \begin{align*} f(x + h)-f(x)&=(x^{2}+2xh+h^{2}-9x - 9h+5)-(x^{2}-9x + 5)\ &=x^{2}+2xh+h^{2}-9x - 9h+5 - x^{2}+9x - 5\ &=2xh+h^{2}-9h \end{align*} ]
Step3: Find the difference quotient
[ \begin{align*} \frac{f(x + h)-f(x)}{h}&=\frac{2xh+h^{2}-9h}{h}\ &=\frac{h(2x + h-9)}{h}\ &=2x+h - 9 \end{align*} ]
Answer:
$2x+h - 9$