LinuxQuestions.org - GCC Compiling (Linux), "Segmentation Fault"

I'm trying to write a program to solve the quadratic exuation and find the vertex. I managed to get it to compile in both the GCC and the G++ (It's written in C), but I can't get it to actually run. Right after entering the first number, it gets a segmentation fault.
Konsole:

Code:

[neil@localhost ~]$ gcc '/home/neil/Desktop/calc.c' -o '/home/neil/Desktop/calc.exe' -lm

[neil@localhost ~]$ '/home/neil/Desktop/calc.exe'

Welcome to my quadratic program,

 the Quradratic Calculator;

The format is =_x^2 + _x + _

=2

Segmentation fault

Source:

Code:

#include <stdio.h>

#include <math.h>

float quad1(int x1, int x2, int x3);

float quad2(int x1, int x2, int x3);

float med(float y1, float y2);

float val(float z1, float z2, float z3, float mid);





int main()

{

        int ax, bx, cx;

        float y1, y2, mid, mival;

        printf("Welcome to my quadratic program,\n the Quradratic Calculator;\nThe format is =_x^2 + _x + _\n=");

        scanf("%d", ax);

        printf("x^2 +");

        scanf("%d", bx);

        printf("x + ");

        scanf("%d", cx);

        y1 = quad1(ax, bx, cx);

        y2 = quad1(ax, bx, cx);

        mid = med(y1, y2);

        mival = val(ax, bx, cx, mid);

        printf("The 0s are (%f, 0) and (%f, 0)\nThe vertex is (%f, %f).\n", y1, y2, mid, mival);

        return 0;

}



float quad1(int x1, int x2, int x3)

{

        float y;

        y = (-x2 + sqrt( pow(x2, 2) - 4 * (x1 * x3)))/(2 * x1);

        return y;

}



float quad2(int x1, int x2, int x3)

{

        float y;

        y = (-x2 - sqrt( pow(x2, 2) - 4 * (x1 * x3)))/(2 * x1);

        return y;

}



float med(float y1, float y2)

{

        float median;

        median = (y1+ y2)/2;

        return median;

}



float val(float z1, float z2, float z3, float mid)

{

        float mima;

        mima = (z1 * pow(mid, 2)) + (z2 * mid) + z3;

        return mima;

}

Segmentation faults have caused delays with my programming before. What do they mean? How can I fix this one?