Answer:
Between 10 and 11.
Explanation:
To begin, we can look at the problem as such. If we take the first answer choice, we can find the squares of both numbers giving us: (Remember that the area of a square is A=L²)
10²= 100
11²= 121
Since the given area is in between these two numbers, this means that the side length must be between 10 and 11.