$$ \begin{aligned}2y(y-4)& \xlongequal{ \color{blue}{ \text{\normalsize{ \htmlClass{explanationCircle explanationCircle1}{\textcircled {1}} } }}}2y^2-8y\end{aligned} $$ | |
① | Multiply $ \color{blue}{2y} $ by $ \left( y-4\right) $ $$ \color{blue}{2y} \cdot \left( y-4\right) = 2y^2-8y $$ |