| $$ \begin{aligned}2\sqrt{529}& \xlongequal{ \color{blue}{ \text{\normalsize{ \htmlClass{explanationCircle explanationCircle1}{\textcircled {1}} } }}}2\cdot23 \xlongequal{ } \\[1 em] & \xlongequal{ }46\end{aligned} $$ | |
| ① | The square root of $ 529 $ is $ 23 $. |