Evaluate
4\sqrt{5}\approx 8.94427191
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\frac{20\sqrt{5}}{\left(\sqrt{5}\right)^{2}}
Rationalize the denominator of \frac{20}{\sqrt{5}} by multiplying numerator and denominator by \sqrt{5}.
\frac{20\sqrt{5}}{5}
The square of \sqrt{5} is 5.
4\sqrt{5}
Divide 20\sqrt{5} by 5 to get 4\sqrt{5}.
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