The equation d = rt relates the distance d you travel, the time / it takes to travel that distance, and the rate rat which you travel. So the time it takes is t = d/r If you increase your rate by a to r+a, then it takes less time, t = d/r+a In fact, the time you save by going faster is T = d/r - d/r+a

You normally take a 500-mi trip, averaging 45 mi/h. You want to increase the rate so that your travel time is at least 1 h shorter. Write an inequality that describes the situation.