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