Answer:
Length of the fence will be = 282.84 feet
Explanation:
The Blackburn family has a square field to keep their cattle. Area of the field is $40000 square feet.
Then one side of the square field will be = √Area = √40000 = 200 feet
Since diagonal of a square is = √2(side)² = side√2 = 200√2 = 200×1.41 = 282.84 feet.
Therefore length of the fence will be = 282.84 ft.