| $$ \begin{aligned}1+3x+5& \xlongequal{ \color{blue}{ \text{\normalsize{ \htmlClass{explanationCircle explanationCircle1}{\textcircled {1}} } }}}3x+6\end{aligned} $$ | |
| ① | Combine like terms: $$ \color{blue}{1} +3x+ \color{blue}{5} = 3x+ \color{blue}{6} $$ |