Answer
$$ f(5+h)=\sqrt{5+h}$$
$$\frac{f(a+h)-f(a)}{h} =\sqrt{6}-\sqrt{5}$$
Work Step by Step
Since $ f(x)=\sqrt{x}$, then $ f(5+h)=\sqrt{5+h}$.
The quotient difference is given by
$$\frac{f(a+h)-f(a)}{h}=\frac{f(6)-f(5)}{1}=\sqrt{6}-\sqrt{5}=\sqrt{6}-\sqrt{5}$$