If one side of a square notebook measures 20 cm, what is the area of the front cover of the notebook?
40 centimeters squared
80 centimeters squared
200 centimeters squared
400 centimeters squared
Since a square has all equal sides, this would mean the the all the other sides are 20 as well. To get the area, you would just multiply 20 by 20 to get 400. :)
