| $$ \begin{aligned}20\sqrt{36}& \xlongequal{ \color{blue}{ \text{\normalsize{ \htmlClass{explanationCircle explanationCircle1}{\textcircled {1}} } }}}20\cdot6 \xlongequal{ } \\[1 em] & \xlongequal{ }120\end{aligned} $$ | |
| ① | The square root of $ 36 $ is $ 6 $. |