HW 7.b

#include <iostream>
using namespace std;
void Intersection(int a1, int b1, int c1, int a2, int b2, int c2, int& xv,int &yv)
{
    if (((a1 == 0) && (b1 == 0)) || ((a2 == 0)&&(b2 == 0)))
        cout << "there is no such direct";
    else if ((a1 / a2) == (b1 / b2)&&((a1 / a2) == (c1 / c2)))
        cout << "   Straight lines coincide";
    else if ((a1 / a2) == (b1 / b2)&&((b1 / b2) != (c1 / c2)))
        cout << "parallel";
    else if ((a1 / a2) != (b1 / b2))
    {
        cout << "intersect";
        xv = (-1)*(c1*b2 - c2*b1) / (a1*b2 - a2*b1);
        yv = (-1)*(c2*a1 - c1*a2) / (a1*b2 - a2*b1);
    }
}
    int main ()
    {
        int a1,a2,b1,b2,c1,c2,c3,a3,b3,vx1,vy1,vx2,vy2,vx3,vy3;
        double s;
        cin >> a1 >> b1 >> c1;
    cin >> a2 >> b2 >> c2;
    cin >> a3 >> b3 >> c3;
     Intersection(a1, b1, c1,a2,b2, c2,vx1,vy1);
     Intersection(a1, b1, c1, a3, b3, c3,vx2,vy2);
     Intersection(a2, b2, c2, a3, b3, c3,vx3,vy3);
     s = 1 / 2 * ((vx1 - vx3)*(vy2 - vy3) - (vy1 - vy3)*(vx2 - vx3));
     cout << "s=" << s;

     system("pause");
     return 0;

}