Question 921124
area  = 66 m^2
let x,y be the length and width of rectangle 
 as per the data  x = 3*y-7
   But area X*Y   =66 m^2
          substitute  x=  3y-7 in above equation
           (3y-7)*y  = 66
          3y*y-7*y  =66
         3y^2 -7y=66
   subtract 66 on both sides
     3y^2 -7y-66 =66-66
      3y^2-7y -66 =0*[invoke quadratic "y", 3, -7, -66 ]
   But Y cannot be negative 
  hence  y =6
    x= 3*6-7
      =18-7
      =11
length  = 11  m
 width   = 6 m