$$
\begin{array}{l} 
1.19=1 \times 9+(1+9) \\
29=2 \times 9+(2+9) \\
39=3 \times 9+(3+9) \\
49=4 \times 9+(4+9) \\
\ldots \ldots \\
189=18 \times 9+(18+9)
\end{array}
$$

Then
【Answer】 $\overline{A 9}=10 A+9=9 A+(A+9)$, where $\mathbf{A}$ is a positive integer 【Analysis】Key point: Identifying patterns