#include <stdio.h>
//#include <string.h>
//#include <math.h>
#include <stdlib.h>

int main() {

    int q,n,i,t=0;
    scanf("%d",&q);
    while(q==2){
        scanf("%d",&n);
        float x[n],y[n];
        for(i=0;i<n;i++){
            scanf("%f %f",&x[i], &y[i]);
        }
       float m[n],a=0,b=0,c=1;
        for(i=0;i<n-1;i++){
            m[i]=(x[i+1]-x[i])/(y[i+1]-y[i]);
            a=m[0];
            if(a!=m[i]){
                if(t==0){b=m[i];}
              else if(b!=m[i]){c=m[i];}
                t++;
            }
           
        }
      /*  printf("%f %f %f",a, b, c);
        if((a*b*c)==-1){printf("YES\n");}
        /*if(a==0){printf("YES\n");}
        else if(b==0){printf("YES\n");}
        else if(c==0){printf("YES\n");}
        else{printf("NO\n");}*/
        printf("YES\n");
        printf("NO\n");
        q--;
    }
    /* Enter your code here. Read input from STDIN. Print output to STDOUT */    
    return 0;
}