Please help asap. Really would appreciate it

Step-by-step explanation:
We got
[tex] \frac{f(x + h) - f(x)}{h} [/tex]
The function here is
9x^2 so we got now
[tex] \frac{9(x + h) {}^{2} - 9 {x}^{2} }{h} [/tex]
[tex] \frac{9( {x}^{2} + 2hx + {h}^{2} - 9 {x}^{2} }{h} [/tex]
[tex] \frac{9 {x}^{2} + 18hx + 9 {h}^{2} - 9 {x}^{2} }{h} [/tex]
Cancel out terms.
[tex] \frac{18hx + 9h {}^{2} }{h} [/tex]
If we direct subsitue we get
[tex] \frac{0}{0} [/tex]
which is intermidate form in calculus so now, let try to find another way to evaluate this, we can factor out 9h
[tex] \frac{9h(2x + h}{h} [/tex]
Cancel out h
[tex]9(2x + h)[/tex]
Subsitue 0 for h.
[tex]9(2x + 0)[/tex]
[tex]9(2x)[/tex]
[tex]18x[/tex]
The answer here is 18x.
Congrats. We just found the derivative of a function.