Arithmetic Expression With Quadratic Formula

I have just started to learn programming in the book I am teaching myself from it said how would you write the following arithmetic expression with it being the quadratic formula but only the plus part of it in the plus or minus..

package javalearning;
import java.util.Scanner;
public class QuadraticFormula {
public static void main(String[] args){
Scanner input = new Scanner(System.in);
System.out.print("Enter value for B: ");
double B = input.nextDouble();
System.out.print("Enter value for A: ");
double A = input.nextDouble();
System.out.print("Enter value for C: ");
double C = input.nextDouble();
double negativeOfB = -B;

[code]....