Tap the blue circles to see an explanation.
$$ \begin{aligned}\frac{4}{\sqrt{63}}& \xlongequal{ \color{blue}{ \text{\normalsize{ \htmlClass{explanationCircle explanationCircle1}{\textcircled {1}} } }}} \frac{ 4 }{\sqrt{ 63 }} \times \frac{ \color{orangered}{\sqrt{ 63 }} }{ \color{orangered}{\sqrt{ 63 }}} \xlongequal{ } \\[1 em] & \xlongequal{ \color{blue}{ \text{\normalsize{ \htmlClass{explanationCircle explanationCircle2}{\textcircled {2}} } }}}\frac{4\sqrt{63}}{63} \xlongequal{ } \\[1 em] & \xlongequal{ \color{blue}{ \text{\normalsize{ \htmlClass{explanationCircle explanationCircle3}{\textcircled {3}} } }}} \frac{ 4 \sqrt{ 9 \cdot 7 }}{ 63 } \xlongequal{ } \\[1 em] & \xlongequal{ } \frac{ 4 \cdot 3 \sqrt{ 7 } }{ 63 } \xlongequal{ } \\[1 em] & \xlongequal{ }\frac{12\sqrt{7}}{63} \xlongequal{ } \\[1 em] & \xlongequal{ \color{blue}{ \text{\normalsize{ \htmlClass{explanationCircle explanationCircle4}{\textcircled {4}} } }}} \frac{ 12 \sqrt{ 7 } : \color{blue}{ 3 } }{ 63 : \color{blue}{ 3 } } \xlongequal{ } \\[1 em] & \xlongequal{ }\frac{4\sqrt{7}}{21}\end{aligned} $$ | |
① | Multiply both top and bottom by $ \color{orangered}{ \sqrt{ 63 }}$. |
② | In denominator we have $ \sqrt{ 63 } \cdot \sqrt{ 63 } = 63 $. |
③ | Simplify $ \sqrt{ 63 } $. |
④ | Divide both the top and bottom numbers by $ \color{blue}{ 3 }$. |