#include<iostream>
using namespace std;

int main()
{
    int n;
    int sum;
    int mul;
    cin>>n;
    for(int i =0; i<n; i++)
    {
            cin>>sum>>mul;
            if(sum<mul)
            cout<<"impossible"<<endl;
            else if((sum-mul)%2==0)
            cout<<(sum+mul)/2<<" "<<(sum-mul)/2<<endl;
            else cout<<"impossible"<<endl;//如果s-d是奇数也是impossible……
    }
     return 0;
}