Respuesta :

Answer:

18

Step-by-step explanation:

the square root of 81 is 9, because 9x9 is 81.

now we do (9x2)

=18

Answer: It is 9

Step-by-step explanation:

A square root is a number that has to be multiplied by itself to the number your looking for. So, 9 X 9 = 81.