Tap the blue circles to see an explanation.
$$ \begin{aligned}\frac{3\sqrt{7}}{\sqrt{20}}& \xlongequal{ \color{blue}{ \text{\normalsize{ \htmlClass{explanationCircle explanationCircle1}{\textcircled {1}} } }}}\frac{3\sqrt{7}}{\sqrt{20}}\frac{\sqrt{20}}{\sqrt{20}} \xlongequal{ } \\[1 em] & \xlongequal{ \color{blue}{ \text{\normalsize{ \htmlClass{explanationCircle explanationCircle2}{\textcircled {2}} } }}}\frac{6\sqrt{35}}{20} \xlongequal{ } \\[1 em] & \xlongequal{ \color{blue}{ \text{\normalsize{ \htmlClass{explanationCircle explanationCircle3}{\textcircled {3}} } }}}\frac{ 6 \sqrt{ 35 } : \color{blue}{ 2 } } { 20 : \color{blue}{ 2 }} \xlongequal{ } \\[1 em] & \xlongequal{ }\frac{3\sqrt{35}}{10}\end{aligned} $$ | |
① | Multiply the numerator and denominator by the conjugate of the denominator . $$\color{blue}{ \sqrt{20}} $$. |
② | Multiply in a numerator. $$ \color{blue}{ 3 \sqrt{7} } \cdot \sqrt{20} = 6 \sqrt{35} $$ Simplify denominator. $$ \color{blue}{ \sqrt{20} } \cdot \sqrt{20} = 20 $$ |
③ | Divide numerator and denominator by $ \color{blue}{ 2 } $. |