How do you find the square root of 25?

1 Answer
Jan 25, 2017

#sqrt(25) = 5#

Explanation:

A square root of a number #n# is a number #r# such that #r^2 = n#

In the case of #25# we find that #5^2 = 25#, so #5# is a square root of #25#.

Note that #-5# is also a square root of #25#, in that:

#(-5)^2 = (-5)xx(-5) = 25#

"The" square root usually refers to the positive square root, sometimes known as the principal square root.

In symbols, we write:

#sqrt(25) = 5#

Note that #sqrt(...)# refers to the principal square root. If we want to say that either square root can be used, we could write #+-sqrt(...)#