Question

Problem a (LA2a.java) Write a program to compute the area, perimeter, and interior angle of a regular polygon. First, have the user supply the number of sides of the polygon (a whole number, which must be 3 or greater) and the side length (any positive number). Then, compute the area via the following equation: where n is the number of sides and s is the side length. Note that the equations are equivalent, with the first using degrees and the second using radians. Then, compute the perimeter via the following equation: and then the interior angle (in degrees) via the following equation: So, an example run of your program would look like the following: (texts marked with blue color are the user’s input.) Enter number of sides: 3 Enter side length: 1 Area: 0.433 Perimeter: 3.000 Interior Angle: 60.000 degrees You should express the outputs using exactly three decimal places (rounding where necessary). Tips: (i) the Math.tan() method will compute the tangent of a value in radians, (ii) the Math.toRadians() method will convert a value in degrees to radians, and (iii) the Math.PI constant can be used for pi (π). Area = s2n 4tan( 180 n ) = s2n 4tan( ⇡ n ) Perimeter = ns Interior Angle = 180 360

*****Make sure error messages println in console and the program stops when less than 3 sides are entered or when negative numbers are entered

******make sure the word degrees is outputted after the value of Interior angle is given

Answer 1

Program

import java.util.Scanner;
public class Main
{
   public static void main(String[] args) {
   int n,s;
   double per,iAngle, area;
   Scanner in = new Scanner(System.in);
       System.out.print("Enter number of sides: ");
       n=in.nextInt();
       if(n<3)
       {
       System.out.println("Invalid sides");
       System.exit(0);
       }
       System.out.print("Enter side length:");
s=in.nextInt();
       if(s<1)
       {
       System.out.println("Invalid sides");
       System.exit(0);
       }
       double t=Math.toRadians(180/n);
       area= (s*s*n)/(4*Math.tan(t));
       per=n*s;
       iAngle= (n-2)*180/n;
   System.out.print("Area: "); System.out.format("%.3f", area);
   System.out.print("\nPerimeter: "); System.out.format("%.3f", per);
   System.out.print("\nInterior Angle: "); System.out.format("%.3f", iAngle); System.out.print(" degrees");
   }
      
}