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Thread: Need some help.

  1. #1
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    Default 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.

  2. #2
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    Default Re: Need some help.

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

  3. #3
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    Default

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

  4. #4
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    Default Re: Need some help.

    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

  5. #5
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    Default

    Thank you