Answer :

Well, you can put 200 into your calculator and find the square root which would be 14.1. Your sides are approximately 14.1 sq.ft long.
nashty
Area = length x width
Area of a Square = length²

Area = 200

200 = L²

√200 = √L²

L = √200

L = 14.142135623730950488016887242097

L = 14.1