 
       
      
    All the angles of a quadrilateral are equal. What special name is given to this quadrilateral?
We know that the sum of all angles of a quadrilateral is 
If PQRS is a quadrilateral,
     …..(1)
It is given that all the angels are equal
i.e., 
Put in equation 1 we get
Here all the angles of a quadrilateral are .
Hence the quadrilateral is either a rectangle or square. We cannot say which one it is, as nothing is given about the length of the sides.  
