| $$ \begin{aligned}4x^5+3x-5y+y+2x& \xlongequal{ \color{blue}{ \text{\normalsize{ \htmlClass{explanationCircle explanationCircle1}{\textcircled {1}} } }}}4x^5+5x-4y\end{aligned} $$ | |
| ① | Combine like terms: $$ 4x^5+ \color{blue}{3x} \color{red}{-5y} + \color{red}{y} + \color{blue}{2x} = 4x^5+ \color{blue}{5x} \color{red}{-4y} $$ |