JAVA方程的解编译问题求解答

为什么两个带不带括号输出结果都一样，但是放到pta上就不对呢

import java.util.Scanner;
class QuadraticEquation{
public double a;
public double b;
public double c;

public QuadraticEquation(double a,double b,double c) {
    this.a = a;
    this.b = b;
    this.c = c;
}
public double getA() {
    return a;
}
public double getB() {
    return b;
}
public double getC() {
    return c;
}
public double getDiscriminant() {
    double discriminant = b*b - 4*a*c;
    return discriminant;
}
public double getRoot1() {
    if (getDiscriminant() < 0)
        return 0;
    else {
        double root1 = (-b + Math.sqrt(getDiscriminant())) / 2 * a;
        return root1;
    }
}
public double getRoot2() {
    if (getDiscriminant() < 0)
        return 0;
    else {
        double root2 = (-b - Math.sqrt(getDiscriminant())) / 2 * a;
        return root2;
    }
}

}

public class Main {
public static void main(String[] args) {
Scanner scanner = new Scanner(System.in);

   int a = scanner.nextInt();
   int b = scanner.nextInt();
   int c = scanner.nextInt();
   int a1 = scanner.nextInt();
   int b1 = scanner.nextInt();
   int c1 = scanner.nextInt();
   QuadraticEquation equation = new QuadraticEquation(a,b,c);
   System.out.println("equation discriminant is:"+(Math.pow(equation.getB(),2)-4*equation.getA()*equation.getC()));
   if (equation.getDiscriminant() < 0){
       System.out.println("The equation has no roots");
   }else{
       System.out.println("equation root1:"+equation.getRoot1());
       System.out.println("equation root2:"+equation.getRoot2());
   }

   QuadraticEquation equation1 = new QuadraticEquation(a1,b1,c1);
   System.out.println("equation1 discriminant is:"+(Math.pow(equation1.getB(),2)-4*equation1.getA()*equation1.getC()));
   if (equation1.getDiscriminant() < 0){
       System.out.println("The equation1 has no roots");
   }else{
       System.out.println("equation1 root1:"+equation1.getRoot1());
       System.out.println("equation1 root2:"+equation1.getRoot2());
   }

}
}

什么带不带括号？没看懂，代码贴全一点，描述清楚一点哪里的括号