Need help on passing values from one method to another

[R .sourav nayak]

hi,
i have twomethod in a java class named polynomail.I wanted to pass the value generated in constructPolynomial()method to displaySelf()method.
How do i do that.Below is the prigram i have written so far.. and even i wanted to findout the value of ax^2+ bx + c in a method named functionvalue().Thank you very much in adavnce

import java.util.Scanner;


class Polynomial {

private double quadratic_co;
private double linear_co;
private double constant;
public Polynomial(){
}
public void constructPolynomial(){
Scanner scan = new Scanner(System.in);
System.out.println("Enter the coefficient of the quadratic term:");
quadratic_co = scan.nextDouble();
System.out.println();
System.out.println("Enter the coefficient of the linear term:");
linear_co = scan.nextDouble();
System.out.println();
System.out.println("Enter the coefficient of the constant term:");
constant = scan.nextDouble();
}
/*public double functionValue(double x,double value, double constant){

value =( (x*x)*quadratic_co) + (x* linear_co)+ constant;
return value;

}*/

public void displaySelf(double quadratic_co, double linear_co, double constant ){

String s = quadratic_co + "x^2 + " + linear_co + "x + " + constant;

System.out.println("Entered Polynomial:f(x)= " + s);

}

}
public class Assi3
{
public static void main(String args[])
{
Polynomial p = new Polynomial();
p.constructPolynomial();
//p.functionValue(4.0);
p.displaySelf();
}
}

[sven studde]

private double generatedValue;
 
constructPolynomial( )
{ 
   ...
   generatedValue = ...;
}
 
displaySelf()
{
   ....
   System.out.println(generatedValue);
}