SOLUTION: dave traveled 280 miles at a certain speed (rate). If he had gone 5 mph faster, the trip would have taken 1 hour less what was his original rate?
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Question 1080740: dave traveled 280 miles at a certain speed (rate). If he had gone 5 mph faster, the trip would have taken 1 hour less what was his original rate? Answer by Alan3354(69443) (Show Source):
You can put this solution on YOUR website! dave traveled 280 miles at a certain speed (rate). If he had gone 5 mph faster, the trip would have taken 1 hour less what was his original rate?
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t = d/r
t = 280/r = (280/(r+5)) + 1
280/r = (280 + r + 5)/(r+5)
280*(r+5) = r^2 + 285r
280r + 1400 = r^2 + 285r
r^2 + 5r - 1400 = 0
(r + 40)*(r - 35) = 0
r = 35 mi/hr
