#include <bits/stdc++.h>

#ifndef ONLINE_JUDGE
    #define DEBUG
    #include <bits/headerfile.hpp>
#else
    #define zqy1018zqy1018zqy1018zqy1018zqy1018 123
#endif

#define INF 2000000000
#define MOD 1000000007
#define MAXN 200005
#define REP(temp, init_val, end_val) for (int temp = init_val; temp <= end_val; ++temp)
#define REPR(temp, init_val, end_val) for (int temp = init_val; temp >= end_val; --temp)

using namespace std;
typedef long long ll;
typedef unsigned long long ull;
typedef pair<int, int> intpair;
int read(){
    int f = 1, x = 0;
    char c = getchar();
    while (c < '0' || c > '9'){if(c == '-') f = -f; c = getchar();}
    while (c >= '0' && c <= '9')x = x * 10 + c - '0', c = getchar();
    return f * x; 
}
inline int lowbit(int x){
    return x & (-x);
}
inline int modadd(int x, int y){
    return (x + y >= MOD ? x + y - MOD: x + y);
}
inline int sgn(int x){
    return (x < 0 ? -1: (x > 0 ? 1: 0));
}
template<typename T>
T gcd(T a, T b){
    return (!b) ? a: gcd(b, a % b);
}
int poww(int a, int b){
    int res = 1;
    while (b > 0){
        if (b & 1) res = 1ll * res * a % MOD;
        a = 1ll * a * a % MOD, b >>= 1;
    }
    return res;
}
const int dx[] = {-1, 0, 1, 0}, dy[] = {0, 1, 0, -1};
const int ddx[] = {-1, -1, -1, 0, 0, 1, 1, 1}, ddy[] = {-1, 0, 1, -1, 1, -1, 0, 1};

/*--------------------------------------------------------------------*/
/*--------------------------------------------------------------------*/

int a, b;
void init(){
    a = read(), b = read();
}
void solve(){
    if (a > b) swap(a, b);
    if (b == 1){
        puts("-1 -1");
        return ;
    }
    if (a == 1){
        if (b == 2) puts("-1 -1");
        else {
            if (b & 1)
                printf("%d %d\n", 2, b - 1);
            else {
                // printf("%d %d\n", 3, b - 1);
            }
        }
        return ;
    }
    if (a == b){
        printf("%d %d\n", 2, b);
        return ;
    }

    int mini = INF, maxi = 0;
    int df = b - a;
    for (int l = 1, r; l <= b; l = r + 1){
        int t1 = a / l;
        int t2 = b / l;
        r = min(t1 > 0 ? a / t1: INF, t2 > 0 ? b / t2: INF);
        int dd = t2 - t1;
        if (dd > 0 && df % dd == 0){
            int pp = df / dd;
            if (pp >= l && pp <= r && pp >= 2)
                mini = min(mini, pp), maxi = max(maxi, pp);
        }
    }
    if (mini == INF) puts("-1 -1");
    else printf("%d %d\n", mini, maxi);
}
int main(){
    int T = read();
    while (T--){
        init();
        solve();
    }
    return 0;
}