Answer: 
Step-by-step explanation:

88 can be rewritten as 8 x 10 and 8 can be rewritten as
making a 2 come out of the root.

10 can be rewritten as 2 x 5.

2*2 can also be rewritten as
making a 2 come out of the root.

We can't keep simplifying the root.
20? I’m not for sure maybe look in the book? That’s the answer I got and it was right