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.