Tap the blue circles to see an explanation.
$$ \begin{aligned}\sqrt{54}-7\sqrt{6}& \xlongequal{ \color{blue}{ \text{\normalsize{ \htmlClass{explanationCircle explanationCircle1}{\textcircled {1}} } }}}3\sqrt{6}-7\sqrt{6} \xlongequal{ } \\[1 em] & \xlongequal{ \color{blue}{ \text{\normalsize{ \htmlClass{explanationCircle explanationCircle2}{\textcircled {2}} } }}}-4\sqrt{6}\end{aligned} $$ | |
① | $$ \sqrt{54} =
\sqrt{ 3 ^2 \cdot 6 } =
\sqrt{ 3 ^2 } \, \sqrt{ 6 } =
3 \sqrt{ 6 }$$ |
② | Combine like terms |