Answer:
3 mi
Explanation:
There are three squares with side a
The area of a square is s^2 where s is the side length
A of the square is a^2
We have three of them so add the areas together
a^2+a^2+a^2 = 3a^2
This is equal to 27
3a^2 = 27
Divide each side by 3
3/3a^2 = 27/3
a^2 = 9
Take the square root of each side
sqrt(a^2) = sqrt(9)
a = 3