Shoutbox

I am a beginner c++ programmer and this is my first program.
I enter:

quote:

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a=5
b=10
c=5

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but it shows
discriminant=-6,9e-018
I thought 10*10-4*5*5=0?

Here my code:

code:

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#include <math.h>
#include <stdio.h>

int wortelformule()
{
   float a,b,c,d,x1,x2;
   printf("ax²+bx+c=0 \n");
   printf("The value of a is ");
   scanf("%g",&a);
   printf("The value of b is ");
   scanf("%g",&b);
   printf("The value of c is ");
   scanf("%g",&c);
   d=pow(b,2)-4*a*c;
   printf("\n \nThe discriminant is %g \n",d);
   x1=(-b+pow(d,0.5))/(2*a);
   x2=(-b-pow(d,0.5))/(2*a);
   printf("The first answer is %g \n",x1);
   printf("The second answer is %g \n \n",x2);
   wortelformule();
}

main()
{
      wortelformule();
}

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