Given the phrasing of your question, that could be a matter of debate.
First, the square root of 72 is actually 8.48528137, at least that is accurate to within 1/10,000,000th.
As far as "simplest" goes, that is the answer.
There is a concept of a "simplified radical form" that you may actually mean.
If so, the answer is 6 times the square root of 2. This represents the fact of 36 times 2 equalling 72, and six being the square root of 36. The square root of 2 starts out as 1.414 and is by no definition "simple", so we simply say "six times the square root of two" as opposed to "six times 1.414...forever in a non-repeating way".
6 root 2
sqrt(72) = 6 sqrt(2)
sqrt(72) = sqrt(36*2) = sqrt(36)*sqrt(2) = 6*sqrt(2).
6√2
The square root of 72 is equivalent to 6 times the square root of 2.
Well, there technically is not a way to simplify the square root of 2, but the simplified version of the square root of 72 is 6 square root 2
sqrt(72) = 6 sqrt(2)
6√2
sqrt(72) = sqrt(36*2) = sqrt(36)*sqrt(2) = 6*sqrt(2).
6 *sqrt(2)
6√2
The square root of 72 is equivalent to 6 times the square root of 2.
Well, there technically is not a way to simplify the square root of 2, but the simplified version of the square root of 72 is 6 square root 2
36
49/72 is in its simplest form.
6 root(2) = root(36) root(2) = root(36 x 2) = root(72).
61/72 is in its simplest form.
67/72 is in its simplest form.