thanks a lot friends and experts i'm very happy to be a part of this science community. anyway

this is a code that i have made

Code:

#include<stdio.h>
#include<math.h>
#include<stdlib.h>
main(void)
{
double a,b,c,d,X1,X2;
printf(" this program can solve equations of degree two");
printf("\n this kind of equations has this format ax˛+bx+c=0");
printf("\n so you have to know the entegers a,b,c before the beginning");
printf("\n please enter the digit a:");
scanf("%lf",&a);
printf("\n please enter the digit b:");
scanf("%lf",&b);
printf("\n please enter the digit c:");
scanf("%lf",&c);
d = (b*b)-(4*a*c);
printf(" this is delta of the equation: %f",d);
if (d < 0);
printf("\nthis equation doesn't have any solution\n");
system("pause");
if(d > 0);
printf("\nthis equation accept a solution\n");
X1=(-b-(sqrt(d)))/(2*a);
X2=(-b+(sqrt(d)))/(2*a);
system("pause");
printf("The solution is X1=%f and X2=%f",X1,X2);
system("pause");

this is the code please help me editing it. thanks a lot