Thread: Need some help.

hello everyone,

I just started to do java and I'm suppose to solve an quadratic equation ax^2+bx+c=0.

So everything works good, and im trying to put some restrictions on the equation like if a=0 do this , if square root=0 do this if both do this.

the restriction works, the only problem is that every time I run the program both message shows off. What should I do?

System.out.println("Finding the solution to ax^2+bx+c=0");
      System.out.println("Write a value for a"); 
      double a = input.nextDouble();
 
      System.out.println("Write a value for b"); 
      double b = input.nextDouble();
      System.out.println("Write a value for c"); 
      double c = input.nextDouble();
      double square = (Math.sqrt(b*b-4*a*c));
      double x1 = (-b+square)/(2*a);
      double x2 = (-b-square)/(2*a);
      double xx1 = (-b+square);
      double xx2 = (-b-square);
 
 
 
 
      if (square > 0)
      {
         System.out.println("x1= " +x1+ "  and x2= "+x2);
      }
 
      else
      {
       System.out.println("Square root is 0 making x1 and x2 =" +-b/2*a);
      }
 
      if (a>0)
      {
         System.out.println("x1 = "+x1+ "   and x2 = "+x2);
      }
      else {
         System.out.println("x1 = "+xx1+ "   and x2 = "+xx2);
   }
 
   }
}

Thank you.

The reason it is printing twice is because you do your check on the square and then on a instead of doing them together.

So I just do them together in the same if or use else if ?

I would. Basically start with your if statement with the square root. Within that block define what happens if a is above 0 and if a is 0 then do the same thing in the else part of your block for the squareroot

Thank you