<h2><em>So, we call 5 the “square root” of 25 and write √25=5 because 52=25 . ... Since (−5)2 also equals 25 it is also a “square root” of 25 , but we write −√25=−5 because it is not the principal square root. Not all whole numbers have a whole number square root. For instance √2=1.414213562…</em></h2>
