| $$ \begin{aligned}6x^2+13-5& \xlongequal{ \color{blue}{ \text{\normalsize{ \htmlClass{explanationCircle explanationCircle1}{\textcircled {1}} } }}}6x^2+8\end{aligned} $$ | |
| ① | Combine like terms: $$ 6x^2+ \color{blue}{13} \color{blue}{-5} = 6x^2+ \color{blue}{8} $$ |