#include<stdio.h> #include<math.h> #include<complex.h> int main() { float a,b,c,x1,x2,de,temp; while(scanf("%f %f %f",&a,&b,&c)!=EOF) { de=b*b-4*a*c; if(a==0) { printf("Not quadratic equation"); } else { if(de>0) { x1=-sqrt((b*b-4*a*c)/(4*a*a))-b/(2*a); x2=sqrt((b*b-...