nine sevenths.
yes
the square root is 7
9
1/2
About 6.32...
Yes.
If you mean square ROOT of 81, 9.
The square roots of 81 are -9 and +9.
12 (the square root of 144).
48 in a square root sign
9 is the square ROOT of 81. Calculating a square root is the inverse operation of squaring a number.
6/7 or 0.857