quadratic equation, problems that i can't solve

[kourai]

import java.io.*;
import javax.swing.JOptionPane;

class RownanieKwadratowe
{
	//static float a, b, c, delta;
	//static String pomocniczy;
	//static double x, x1, x2;
	
	
	public static void main(String[] args)
	{
		float a, b, c;
		String pomocniczy;
		double x, x1, x2, delta;
		
		pomocniczy=JOptionPane.showInputDialog(null, "Podaj wspolczynnik a równania kwadratowego: ");
		a=Float.parseFloat(pomocniczy);
		pomocniczy=JOptionPane.showInputDialog(null, "Podaj wspolczynnik b równania kwadratowego: ");
		b=Float.parseFloat(pomocniczy);
		pomocniczy=JOptionPane.showInputDialog(null, "Podaj wspolczynnik c równania kwadratowego: ");
		c=Float.parseFloat(pomocniczy);
		if (a!=0) 
		{
			delta=(b*b)-(4*a*c);
			if (delta<0) System.out.println("Delta mniejsza od 0. Brak pierwiastkow rzeczywistych.");
			if (delta==0) 
			{
				x=(-b)/(2*a);
				System.out.println("Jeden pierwiastek podwojny x=" + x);
				
			}
			if (delta>0)
			{
			x1=	(-b - Math.sqrt(delta))/2*a;
			x2 =(-b + Math.sqrt(delta))/2*a;
			System.out.println("Dwa pierwiastki rzeczywiste x1="+ x1 + " x2="+ x2);
			}
		}
		else System.out.println("To nie rownanie kwadratowe. Nie mozna liczyc pierwiastkow.");
	
	System.exit(0);
	}
}

here are the errors:
1. Description Resource Path Location Type
Syntax error on token "0", delete this token Zadanie2.java /Zadanie2/src line 47 Java Problem

2. Description Resource Path Location Type
Syntax error on token "Invalid Character", invalid AssignmentOperator Zadanie2.java /Zadanie2/src line 40 Java Problem

3. Description Resource Path Location Type
Syntax error on token(s), misplaced construct(s) Zadanie2.java /Zadanie2/src line 47 Java Problem

4. Description Resource Path Location Type
The left-hand side of an assignment must be a variable Zadanie2.java /Zadanie2/src line 40 Java Problem

i don't know extacly what i did do wrong :/ can you help me? I'm new in java...that's my first program here...

[Eranga]

For the first one, can you post what's there in line 47. I'm lazy to run the code and see.

[JosAH]

[code]
here are the errors:
1. Description Resource Path Location Type
Syntax error on token "0", delete this token Zadanie2.java /Zadanie2/src line 47 Java Problem

The source code you posted has only 46 lines ...

kind regards,

Jos