Is 20 a perfect square number?

1 Answer
Jul 5, 2015

Answer:

No. It's root is #4.4721...#

Explanation:

You could have seen this without calculating in two ways:

#4^2=16# which is too low
#5^2=25# which is too high.

Or:
A square allways ends in an even number of zeroes. Every zero at the end means a factor 10, and in squares every factor is paired.