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