| $$ \begin{aligned}3+6i+4-2i& \xlongequal{ \color{blue}{ \text{\normalsize{ \htmlClass{explanationCircle explanationCircle1}{\textcircled {1}} } }}}4i+7\end{aligned} $$ | |
| ① | Combine like terms: $$ \color{blue}{3} + \color{red}{6i} + \color{blue}{4} \color{red}{-2i} = \color{red}{4i} + \color{blue}{7} $$ |