thanks for the reply. so it was arbitrage trading, maybe i didnt get it in the first place.
in spread trading, there's always the selling of overvalued and buying of undervalued currencies. thus, due to correlationship, the price will eventually move in tandem.
this is an update of the hedge trading. almost 1.3k so far based on 50k, using almost 20% of equity for margin (8 pair, 4 hedges). 2.6% return. will continue to monitor