Answer :
a square will have the same length and width and area= length times width. its set up in a 4x4 square because there are 16 squares total; 4 across and 4 down. if the sides are 4 miles each then one whole side will be 16 miles. so the equation is 16 times 16 which equals 256. so the answer is 256 square miles.
4 miles x 4 sides per district x 16 districs= 256miles in square county