Arectangle has an area of 96 sq ft if the width of the yard is 4 ft less than the length, what is the perimeter in ft of the yard?

The area of a rectangle is obtained through the equation,
  
                                  A = L x W 

The width of the yard is 4 ft less than the length and may be expressed as L - 4. Length may be solved through the following steps,
   
                               A = (L)(L-4)   ; 96 = L(L - 4)    ; L = 12 ft

The length and width are 12 ft and 8 ft, respectively. Perimeter may be solved through the equation,
 
                                           P = 2 x (L + W)

Substituting the values of L and W
 
                                           P = 2 x ( 12 ft + 8 ft) = 40 ft

Therefore, the perimeter of the yard is 40 ft. 

I’d say letter a..