Answer :

MattD
[tex]\sqrt{90}=\sqrt{9*10}=\sqrt{9}*\sqrt{10}=3\sqrt{10}=3*3.16227766=9.486832981[/tex]

Exact element never pull out of an irrational number. They are like mathematical proofs. However, what I wrote is very for a precise approximation.
AnnieA
The exact square root is 9.48683298051
Rounded square root is 9
Hoped I helped:D