import java.util.Scanner;

/**
 * Exercise 4.4 from the book Introduction to Java Programming (10th).
 * <p>
 * Geometry: area of a hexagon.
 *
 * @author Henrik Samuelsson, henrik.samuelsson(at)gmail.com
 */

public class Exercise_04_04 {

	public static void main(String[] args) {
		Double side;	// length of one side in the hexagon
		Double area;	// the area of a hexagon
		
		// query the user for the length of the sides in the hexagon
		Scanner input = new Scanner(System.in);
		System.out.print("Enter the side: ");
		side = input.nextDouble();
		
		// calculate the area of the hexagon using the formula provided in the
		// exercise instructions
		area = (6 * side * side ) / ( 4 * Math.tan(Math.PI/6));
		
		// print the results of the calculation
		System.out.printf("The area of the hexagon is %.2f", area);
	}

}

@@ -308,11 +308,9 @@
  of 
-one
+a
  sid

Update Exercise_04_04.java