homework 3-1

// homework 3
// ex 1
#include <iostream>
#include <cmath>

using namespace std;

int main()
{
  double a;
  double b;
  double c;

  cout<<"a=";
  cin>>a;

  cout<<"b=";
  cin>>b;

  cout<<"c=";
  cin>>c;

  double d;
  d=b*b-4*a*c;
  cout<<"D="<<d<<endl;

  if(d<0)
  {
      cout<<"D<0 roots net"<<endl;
  }

  if(d==0)
  {
      cout<<"D=0 roots est' odin"<<endl;
      double x;
      x=-b/(2*a);
      cout<<"x="<<x<<endl;
  }

  if(d>0)
  {
      cout<<"D>0 roots est' dva"<<endl;
      double x;
      double z;
      x=(-b+sqrt(b))/(2*a);
      cout<<"x1="<<x<<endl;
      z=(-b-sqrt(b))/(2*a);
      cout<<"x2="<<z<<endl;

  }
}