#include<bits/stdc++.h>
using namespace std;
#define int long long
#define f(i,j,k) for(int i=j;i<=k;++i)
#define g(i,j,k) for(int i=j;i>=k;--i)
int n,m,s,l;
struct xy{double x,y;void rd(){cin>>x>>y;}}a[9];
struct ln{double A,B,C;}b[3];
ln F(int i,int j,double r){xy p=a[i],q=a[j];double x=q.x-p.x,y=q.y-p.y;q.x=p.x+x*cos(r)-y*sin(r);q.y=p.y+x*sin(r)+y*cos(r);return{p.y-q.y,q.x-p.x,p.x*q.y-p.y*q.x};}
xy G(int i,int j){ln p=b[i],q=b[j];double z=p.A*q.B-p.B*q.A;return{(p.B*q.C-p.C*q.B)/z,(p.C*q.A-p.A*q.C)/z};}
double chr(xy a,xy b,xy c){return(c.x-a.x)*(b.y-a.y)-(b.x-a.x)*(c.y-a.y);}
double F(double r){f(i,1,3)b[i]=F(i,i+3,r);return fabs(chr(G(1,2),G(2,3),G(3,1)))/2;}
inline void doing(){
	f(i,1,6)a[i].rd();
	printf("%.9lf\n",F(0)+F(acos(-1)/2));
}
signed main(){
	int t;
	cin>>t;
	while(t--)doing();
	return 0;
}