| $$ \begin{aligned}8(2x-5)& \xlongequal{ \color{blue}{ \text{\normalsize{ \htmlClass{explanationCircle explanationCircle1}{\textcircled {1}} } }}}16x-40\end{aligned} $$ | |
| ① | Multiply $ \color{blue}{8} $ by $ \left( 2x-5\right) $ $$ \color{blue}{8} \cdot \left( 2x-5\right) = 16x-40 $$ |