| $$ \begin{aligned}-5radical\cdot75& \xlongequal{ \color{blue}{ \text{\normalsize{ \htmlClass{explanationCircle explanationCircle1}{\textcircled {1}} } }}}-375a^2cdilr\end{aligned} $$ | |
| ① | $$ 5 r a d i c a l \cdot 75 = 375 a^{1 + 1} c d i l r = 375 a^2 c d i l r $$ |