So,
A denominator is rationalized when there are no irrational or imaginary numbers in it. Since the square root of 2 is irrational, we just need to multiply the fraction by the square root of 2 over the square root of 2.
\(\frac{10}{ \sqrt{2} }\)
Multiply the fraction by the square root of 2 over the square root of 2.
\(\frac{10\sqrt{2}}{ \sqrt{2}*\sqrt{2} }\)
Simplify.
\(\frac{10\sqrt{2}}{2}\)
\(5\sqrt{2}\)
The denominator is now 1, which is a rational number.
