Is the square root of 80 rational or irrational?

The square root of 80 is irrational because it cannot be expressed as a fraction of two integers. When simplified, (\sqrt{80}) can be written as (\sqrt{16 \times 5} = 4\sqrt{5}). Since (\sqrt{5}) is irrational, the entire expression (4\sqrt{5}) is also irrational.