The area

//抛物线的顶点公式y=a(x-x1)^2+y1
#include <iostream>
struct node
{
    double x;
    double y;
};
int main()
{
    node p1,p2,p3;
    int n;
    scanf("%d",&n);
    while(n--)
    {
        scanf("%lf%lf%lf%lf%lf%lf",&p1.x,&p1.y,&p2.x,&p2.y,&p3.x,&p3.y);
        // y=a*(x-h)^2+k
        double h=p1.x,k=p1.y;
        double a=(p2.y-k)/((p2.x-h)*(p2.x-h));
        double s=(a*(p3.x-h)*(p3.x-h)*(p3.x-h)/3-a*(p2.x-h)*(p2.x-h)*(p2.x-h)/3+k*(p3.x-p2.x));
        s-=((p2.y+p3.y)*(p3.x-p2.x))/2;
        printf("%.2lf\n",s);    
    }
    return 0;
}