Hi Friend,

Try the following code:

import java.util.*;
import java.text.*;
class  PerimeterOfSquare{
    public static void main(String[] args) 
    {
         DecimalFormat df = new DecimalFormat("##.00");
         Scanner input=new Scanner(System.in);
         System.out.println("Enter Area of Square:");
         double area=input.nextDouble();
         double side=Math.sqrt(area);
         System.out.println("Side of Square is: "+df.format(side));
         double perimeter=4*side;
         System.out.println("Perimeter of Square is: "+df.format(perimeter));

    }
}

Thanks