Here we see a perfect negative correlation between the EURUSD and USD index.
Right now both are facing important levels of shown on the chart.
There's no additional information right now, only the support on the EURUSD chart. Next week will be decisive. We must watch closely the price action of both charts looking for clues about the future direction of the market.
This is just an example, there many other correlations on the market that can help us to enter a trade.