c - Solve quadratic; learning functions; program doesn't return values -

please, take @ program wrote part of assignment after chapter 7 programming in c. program should return roots of quadratic based on values of constants typed in user. program should simple; @ beginner's level. although compiler compile program, output prompting message. after enter 3 values, nothing happens, program ends, , @ terminal. have edited program. , if enter values make discriminant less 0,

please, enter 3 constants of quadratic:    1 2 3 roots imaginary square roots of quadratic are: 

thus main function statement still appears.

if enter other values,

please, enter 3 constants of quadratic:    1 8 2 -0.256970 , -7.743030square roots of quadratic are: 

do see formatting? why happen?

#include <stdio.h> #include <math.h>  float abs_value (float x); float approx_sqrt (float x); float solve_quadratic (float a, float b, float c);  // main function prompts user 3 constant values fill quadratic // ax^2 + bx + c int main(void) {     float a, b, c;      printf("please, enter 3 constants of quadratic:   \n");      if (scanf ("%f %f %f", &a, &b, &c) == 3)         printf("square roots of quadratic are:  \n", solve_quadratic(a,b,c));      return 0; }  // function take absolute value of x used further in square root function float abs_value (float x) {     if (x < 0)         x = - x;     return x; }  // function compute approximate square root - newton raphson method float approx_sqrt (float x) {     float guess = 1;      while (abs_value (pow(guess,2) / x) > 1.001 || abs_value (pow(guess,2) / x) < 0.999)           guess = (x / guess + guess) / 2.0;      return guess; }  // function find roots of quadratic float solve_quadratic (float a, float b, float c) {     float x1, x2;     float discriminant = pow(b,2) - 4 * * c;      if (discriminant < 0)     {         printf("roots imaginary\n");         return -1;     }     else     {         x1 = (-b + approx_sqrt(discriminant)) / (2 * a);         x2 = (-b - approx_sqrt(discriminant)) / (2 * a);     }      return x1, x2; } 

thank you!

if (scanf ("%f %f %f", &a, &b, &c) == 1) 

scanf returns number of arguments succesfully scanned. in case, want 3, not 1.