Answer:
length = 4 cm
Width = 5 cm
Step-by-step explanation:
   Area of rectangle = length * width
length = (x - 3) meters
Width = (x - 2) meter
Area = 20 square meters
 (x - 3)*(x - 2) = 20
Use FOIL method.
  x*x + (x)(-2) + (-3)*x + (-3)*(-2) = 20
             x² -2x  - 3x + 6 =20
     Combine like terms
            x² - 5x + 6  = 20
Now subtract 20 from both side
           x² - 5x + 6 - 20 = 0
              x² - 5x - 14  = 0
Factorize the equation and find the roots
     Sum = -5
  Product = -14
  Factors =  (-7) , 2
When we add (-7) + 2 = -5 and when we multiply (-7)*2 = -14
x² + 2x - 7x - 14 = 0
 x(x + 2) -7(x + 2) = 0
 (x + 2)(x - 7)  = 0
 x - 7 = 0   {Ignore (x + 2 = 0) as measurements wont't be in negative}
x = 7
length = x - 3
     = 7 - 3
  [tex]\sf \boxed{\bf length = 4 \ cm}[/tex]
width = x - 2
     = 7 - 2
  [tex]\sf \boxed{\bf width = 5 \ cm }[/tex]
