| $$ \begin{aligned}2x^2y-4x-8x^2y-3x& \xlongequal{ \color{blue}{ \text{\normalsize{ \htmlClass{explanationCircle explanationCircle1}{\textcircled {1}} } }}}-6x^2y-7x\end{aligned} $$ | |
| ① | Combine like terms: $$ \color{blue}{2x^2y} \color{red}{-4x} \color{blue}{-8x^2y} \color{red}{-3x} = \color{blue}{-6x^2y} \color{red}{-7x} $$ |