#include <cmath>
#include <cstdio>
#include <vector>
#include <iostream>
#include <algorithm>
using namespace std;


int main() {
	int n=0;
	cin>>n;
	int x1,x2,y1,y2,y3,x3;
	float m=0;
	float c1,c2;
	int flag=0,flag1=0;
	for (int i = 0; i < n; ++i)
	{
		int q=0;
		cin>>q;
		if (q<=2)
		{
			cout<<"YES"<<endl;
			for (int j = 0; j < q; ++j)
			{
				cin>>x1>>x2;
			}
		}else{
			cin>>x1>>y1>>x2>>y2;
			if (x1-x2==0)
			{
				m=0;
			}else
				m=(y2-y1)/(x1-x2);
			if (m==0)
			{
				c1=y2;
			}else
				c1=y2*(x2-x1)/(y1-y2)-x2;
			flag=0;
			flag1=0;
			for (int j = 2; j < q; ++j)
			{
				cin>>x3>>y3;
				if(flag==0 && y3!=m*x3+c1){
					flag=1;
					c2=y3-m*x3;
				}
				if (flag==1 && y3!=m*x3+c1 && y3!=m*x3+c2)
				{
					flag1=1;
				}
			}
			if (flag1==0)
			{
				cout<<"YES"<<endl;	
			}else
				cout<<"NO"<<endl;
		}
		
	}
    return 0;
}