Math Problem Solver

$$9 + 10=19$$

$$\begin{aligned} \phantom{0}\mathtt{9}\\ \mathtt{+\phantom{0}}\mathtt{1}\mathtt{0}\\ \hline \mathtt{1}\mathtt{9} \end{aligned}$$

$9$ is the digit in the $10^{0}$ place. $9 \times 10^{0} + 0 \times 10^{0} = 9 \times 10^{0}$.

$1$ is the digit in the $10^{1}$ place. $0 \times 10^{1} + 1 \times 10^{1} = 1 \times 10^{1}$.