import java.io.*;
import java.util.*;
import java.text.*;
import java.math.*;
import java.util.regex.*;

public class Solution {

    static Scanner sc = new Scanner(System.in);
  
   
    static int i(){
        return sc.nextInt();
    }
	
	static int[][] ia(int n){                                     //integer array urf ia()
      int arr[][] = new int[n][2];
        
        for(int i=0;i<n;i++)
        {arr[i][0] = i();
         arr[i][1] = i();}
        return arr;
    }
	
	
    public static void main(String[] args) {
        /* Enter your code here. Read input from STDIN. Print output to STDOUT. Your class should be named Solution. */
        
        int q = i();
        while(q-->0){
            int n = i();
            int a[][] = ia(n);
            
            if(n<=3)
                System.out.println("YES");
            else {
                int f = 0;
                for(int j=3;j<n;j++)
                {
                    if(!(line(a[j][0],a[j][1],a[0][0],a[0][1],a[1][0],a[1][1]) && line(a[j][0],a[j][1],a[1][0],a[1][1],a[2][0],a[2][1]) && line(a[j][0],a[j][1],a[2][0],a[2][1],a[3][0],a[3][1]) && line(a[j][0],a[j][1],a[3][0],a[3][1],a[0][0],a[0][1])))
                    
                    {
                        f = 1;
                        break;
                    }
                }
                if(f==1)
                    System.out.println("NO");
                else
                    System.out.println("YES");
            }
        }
    }
    
    static boolean line(int x,int y,int x1,int y1,int x2,int y2)
    {
        return ((y-y1)*(x1-x2)-(x-x1)*(y1-y2)== 0) ;
    }
}