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