Answer
$y$;
$x=0$;
vertical
Work Step by Step
RECALL:
The logarithmic function $f(x) = \log_b{x}$ is:
(1) increasing from left to right; and
(2) has a domain of $(0, +\infty)$.
Since the value of $x$ is greater than 0, then the graph of the function will be asymptotic to $x=0$ (the y-axis), which is a vertical line.
Thus, the missing expressions in the given statement are:
$y$;
$x=0$;
vertical