Find the roots of a given polynomial

This is a program which finds the roots of a given polynomian in the form of ax²+bx+c, where a, b and c are the inputs given by the user. In this program there is a method check() which checks if the value of the discrimainate is a positive number, if it is positive then we will get real roots. This progam is designed using Java.

import java.util.Scanner;
class poly
{
  int a,b,c;
  double s1,s2,d;
  poly()
  {
    a=b=c=0;
    s1=s2=d=0.0;
  }
  void getit()
  {
    Scanner s=new Scanner (System.in);
    a=s.nextInt();
    b=s.nextInt();
    c=s.nextInt();
  }
  boolean check()
  {
    d=(b*b)-(4.0*a*c);
    if(d>=0.0)
      return true;
    else 
      return false;
  }
  boolean calc()
  {
    
    if(check())
    {
      s1=((-b)+(Math.sqrt(d)))/(2.0*a);
      s2=((-b)-(Math.sqrt(d)))/(2.0*a);
      return true;
    }
    else 
      return false;
  }
  void disp()
  {
    if(calc())
      System.out.println("The Roots are: s1: "+s1+", "+s2);
    else
      System.out.println("The Roots are not Real.");
  }
}
class mainDriver
{
  public static void main(String []args)
  {
    poly p =new poly();
    p.getit();
    p.disp();
  }
}

Description:
In the class poly, getit() method is used to assign the values to a,b, and c. The ckech() confirms whether the discriminate is a positive or a negative, the calc() calculates the value of the roots based on the getit() return value. further the calc() drives the disp() method which prints the result.