SOLUTION: At 10:30 am two planes leave New York, one flying east at 560 km/h and the other flying west at 640 lm/h. At what time will they be 2100 km apart?

Algebra ->  Complex Numbers Imaginary Numbers Solvers and Lesson -> SOLUTION: At 10:30 am two planes leave New York, one flying east at 560 km/h and the other flying west at 640 lm/h. At what time will they be 2100 km apart?      Log On


   

Question 52706: At 10:30 am two planes leave New York, one flying east at 560 km/h and the other flying west at 640 lm/h. At what time will they be 2100 km apart?
Answer by rchill(405) About Me  (Show Source):
You can put this solution on YOUR website!
The equation becomes 640x+560x=2100, where x is the amount of time. Combining the like terms we get 1200x=2100; dividing both sides by 1200, we get x=1.75 hours, which is the same as 1 hour 45 minutes. Therefore, the two planes will be 2100 miles apart at 12:15pm.