#include <stdio.h> #include <math.h> int main() { float a, b, c, x1, x2, w, m, n; while(scanf("%f %f %f", &a, &b, &c) != EOF) { w = b*b - 4*a*c; n = sqrt(-w) / (2*a); m = -b / (2*a); if(a != 0){ if(w==0){ if(m==0){ printf("x1=x2=0.00\n"); }else{ x1 = x2= m; printf("x1=x2=%.2f\n", x1);} }...