Evaluate
5\left(\sqrt{2}+\sqrt{6}\right)\approx 19.318516526
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\frac{20\left(\sqrt{6}+\sqrt{2}\right)}{\left(\sqrt{6}-\sqrt{2}\right)\left(\sqrt{6}+\sqrt{2}\right)}
Rationalize the denominator of \frac{20}{\sqrt{6}-\sqrt{2}} by multiplying numerator and denominator by \sqrt{6}+\sqrt{2}.
\frac{20\left(\sqrt{6}+\sqrt{2}\right)}{\left(\sqrt{6}\right)^{2}-\left(\sqrt{2}\right)^{2}}
Consider \left(\sqrt{6}-\sqrt{2}\right)\left(\sqrt{6}+\sqrt{2}\right). Multiplication can be transformed into difference of squares using the rule: \left(a-b\right)\left(a+b\right)=a^{2}-b^{2}.
\frac{20\left(\sqrt{6}+\sqrt{2}\right)}{6-2}
Square \sqrt{6}. Square \sqrt{2}.
\frac{20\left(\sqrt{6}+\sqrt{2}\right)}{4}
Subtract 2 from 6 to get 4.
5\left(\sqrt{6}+\sqrt{2}\right)
Divide 20\left(\sqrt{6}+\sqrt{2}\right) by 4 to get 5\left(\sqrt{6}+\sqrt{2}\right).
5\sqrt{6}+5\sqrt{2}
Use the distributive property to multiply 5 by \sqrt{6}+\sqrt{2}.
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