Question

is √20 a rational or irrational number ?explain how you know

Answer 1

The square root of 20 is irrational.
42 is 16, less than 20 and 52 is 25, more than 20.

Answer 2

√20=√4*√5=2√5
√5-is a irrational number 
===>2√5-is a irrational number =>√20 is a irrational number. :D
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