Tap the blue circles to see an explanation.
$$ \begin{aligned}\frac{5\sqrt{15}}{2\sqrt{20}}& \xlongequal{ \color{blue}{ \text{\normalsize{ \htmlClass{explanationCircle explanationCircle1}{\textcircled {1}} } }}}\frac{5\sqrt{15}}{2\sqrt{20}}\frac{\sqrt{20}}{\sqrt{20}} \xlongequal{ } \\[1 em] & \xlongequal{ \color{blue}{ \text{\normalsize{ \htmlClass{explanationCircle explanationCircle2}{\textcircled {2}} } }}}\frac{50\sqrt{3}}{40} \xlongequal{ } \\[1 em] & \xlongequal{ \color{blue}{ \text{\normalsize{ \htmlClass{explanationCircle explanationCircle3}{\textcircled {3}} } }}}\frac{ 50 \sqrt{ 3 } : \color{blue}{ 10 } } { 40 : \color{blue}{ 10 }} \xlongequal{ } \\[1 em] & \xlongequal{ }\frac{5\sqrt{3}}{4}\end{aligned} $$ | |
① | Multiply the numerator and denominator by the conjugate of the denominator . $$\color{blue}{ \sqrt{20}} $$. |
② | Multiply in a numerator. $$ \color{blue}{ 5 \sqrt{15} } \cdot \sqrt{20} = 50 \sqrt{3} $$ Simplify denominator. $$ \color{blue}{ 2 \sqrt{20} } \cdot \sqrt{20} = 40 $$ |
③ | Divide numerator and denominator by $ \color{blue}{ 10 } $. |