Question 495018
     If its an area of a square then this is correct. 

     AREA OF A SQUARE = L  ×  L

       16FT^2  = L^2

     L  =  THE SQUARE ROOT OF 16

        L  = 4FT

    : EACH SIDES ARE 4FT × 4FT long


     NOTE :  If multiplied 4 × 4 = 16