Answer 1

`4/3`

Explanation;

Hint:

`sqrt(9^x) = root(3)(9^2)`

⇒ `(9^x)^(1/2) = (9^2)^(1/3)`

⇒ `9^(x/2) = 9^(2/3)`

`x/2 = 2/3`

3x = 4

 x = `4/3`