Tap the blue circles to see an explanation.
| $$ \begin{aligned}3\sqrt{5}-3\sqrt{5}\cdot4+3\sqrt{24}& \xlongequal{ \color{blue}{ \text{\normalsize{ \htmlClass{explanationCircle explanationCircle1}{\textcircled {1}} } }}}3\sqrt{5}-12\sqrt{5}+6\sqrt{6} \xlongequal{ } \\[1 em] & \xlongequal{ \color{blue}{ \text{\normalsize{ \htmlClass{explanationCircle explanationCircle2}{\textcircled {2}} } }}}-9\sqrt{5}+6\sqrt{6}\end{aligned} $$ | |
| ① | $$ 3 \sqrt{24} =
3 \sqrt{ 2 ^2 \cdot 6 } =
3 \sqrt{ 2 ^2 } \, \sqrt{ 6 } =
3 \cdot 2 \sqrt{ 6 } =
6 \sqrt{ 6 } $$ |
| ② | Combine like terms |