Answer: The solution to the above expression is 10.
It is not extraneous solution, as it not satisfying the equation.
Explanation:
Since we have given that
3 square root x+6 =-12
that means,

We just need to find the value of x:

Hence, the solution to the above expression is 10.
Now, we have to check whether it is extraneous solution or not.
Put x= 10 in the above expression,

Hence, it is not extraneous solution, as it not satisfying the equation.