Answer:
12
Explanation:
The LCM of 9 and x = 36
The GCD is 3, that means the number has to be divisible by 3 as well.
We can look at all the factors of 36, and see which numbers fit the description
36 = 1, 2, 3, 4, 6, 9, 12, 18, 36
1: Does not have a GCD of 3
2: Does not have a GCD of 3
3: Has a GCD of 9, but LCM is 3, not 36
4: Does not have a GCD of 3
6: Has a GCD of 3, but LCM is 18, not 36
9: Number is given
12: Has GCD of 3, and LCM is 36
18: Has GCD of 9
36: Has GCD of 9
The only number that works is 12, with a GCD of 3, and an LCM of 36
-Chetan K