Answer
$1-\log_{9}{x}$
Work Step by Step
RECALL:
(i) $\log_b{\frac{M}{N}}=\log_b{M} - \log_b{N}$ (Quotient Rule).
(ii) $\log{x}=\log_{10}{x}.$
(iii) $\log_b{b}=1.$
Use the quotient rule with $M=9$ and $N=x$ to obtain
$\log_9{9} - \log_9{x}.$
Use rule (iii) above to obtain
$1-\log_{9}{x}.$