#include <stdio.h>
#include <stdlib.h>

int main(void)
{
char var[] = { 'x', 'y', 'z', 'w' };
printf("Enter the number of variables in the equations: ");
int n;
scanf("%d", &n);
printf("\nEnter the coefficients of each variable for each equations");
printf("\nax + by + cz + ... = d");
int mat[n][n];
int constants[n][1];
int i,j;
for (int i = 0; i < n; i++) {
for (int j = 0; j < n; j++) {
scanf("%d", &mat[i][j]);
}
scanf("%d", &constants[i][0]);
}

printf("Matrix representation is: ");
for (i = 0; i < n; i++) {
for (j = 0; j < n; j++) {
printf(" %f", mat[i][j]);
}
printf(" %f", var[i]);
printf(" = %f", constants[i][0]);
printf("\n");
}
return 0;
}

Output:

$ gcc MatRepOfEquation.cpp
$ ./a.out

Enter the number of variables in the equations: 3

Enter the coefficients of each variable for each equations
ax + by + cz + ... = d
1 2 3 4
1 2 6 8
2 3 9 8
Matrix representation is:
1 2 3 x = 4
1 2 6 y = 8
2 3 9 z = 8