SOLVE IN TERMS OF TWO VARIABLES: A pilot flies a distance of 600 km. He could fly the same distance in 30 minutes less time by increasing his average speed by 40 km/hr. Find his actual average speed. Let x = actual average speed, _____= new average speed, _____= time to fly 600 km at actual average speed, _____= time to fly 600 km at new average speed, _____= difference in time using the two speeds,equation:_________________=____________