#include<bits/stdc++.h>
using namespace std;

#define _ ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0);
#define P(a,n) for(int i=a;i<=n;i++) cout<<a[i]<<" "; 
#define bp(n) __builtin_popcount(n);
#define D 1000000007
#define pb push_back
#define ci(x) cin>>x;
#define c2(x,y) cin>>x>>y;
#define c3(x,y,z) cin>>x>>y>>z;
#define p2(x,y) cout<<x<<" "<<y<<endl;
#define p3(x,y,z) cout<<x<<" "<<y<<" "<<z<<endl;
#define co(x) cout<<x<<endl;
#define r0 return 0;
#define r1 return 1;
#define fi first
#define se second
#define mp make_pair

typedef vector<int> VI;
typedef long double ld;
typedef long long ll;
typedef pair<int,int> pii;
typedef pair<ll,ll> pll;
typedef vector<pii> VII;
typedef vector<ll> VL;
typedef vector<pll> VLL;
ll tpp = 9e18; int tp = 1e9;
int n,q;
VLL a;
int ISO(int x,int y,int z)
{
	return (a[y].fi - a[x].fi)*(a[y].fi - a[z].fi) + (a[y].se - a[x].se)*(a[y].se - a[z].se) == 0;
}
int ISR(int i,int j,int k,int l)
{
	return ISO(i,j,k) and ISO(j,k,l) and ISO(l,k,i);
}

int ISRO(int i,int j,int k,int l)
{
	return ISR(i,j,k,l) || ISR(j,k,l,i) ||ISR(k,i,j,l);
}
int main()
{
	_
	ci(q);
	
	for(int i=1;i<=q;i++)
	{
		ci(n);
		for(int i=1;i<=n;i++)
		{
			int x,y;
			c2(x,y);
			a.pb(mp(x,y));			
		}
		if(a.size() <= 2)
		{
			co("NO");
			continue;
		}
		if(a.size() == 3)
		{
			if(ISO(0,1,2) || ISO(1,2,0) || ISO(2,0,1) == 1)
				cout<<"YES"<<endl;
			else co("NO");
			continue;
		}
		int r=0;
		for(int i=0;i<a.size();i++)
		{
			for(int j=0;j<a.size();j++)
			{
				if(i!=j)
				{
					for(int k=0;k<a.size();k++)
					{
						if(j!=k and k!=i)
						{
							for(int l=0;l<a.size();l++)
							{
								if(k!=l and k!=j and k!=i)	
									int r = ISRO(i,j,k,l);
							}
						}
					}
				}
			}
		}
		if(r == 1) cout<<"YES"<<endl;
		else co("NO");
	}
	r0;
}