Answer:

Work Shown:

Step-by-step explanation:
Rewrite 108 as 36*3, so that we pull out the largest perfect square factor possible. Then we use the rule
to break up the square root. The same idea will be used to simplify the other square root.
We can combine like terms once each individual root is simplified. If it helps, replace each
with x so we have 6x+3x turn into 9x. Then replace x with
to wrap things up.
Using a calculator,

and also

We get the same approximation to help partially confirm the answer.