| $$ \begin{aligned}(-6+8)x^2& \xlongequal{ \color{blue}{ \text{\normalsize{ \htmlClass{explanationCircle explanationCircle1}{\textcircled {1}} } }}}2x^2\end{aligned} $$ | |
| ① | Combine like terms: $$ \color{blue}{-6} + \color{blue}{8} = \color{blue}{2} $$ |