<PRE><B>Question 193777</B>
 Steve traveled 150 miles at a certain speed. Had he gone 20mph faster, the trip would have taken 2 hours less. Find the speed of his vehicle. 
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d = rt
150 = rt
150 = (r+20)*(t-2)
rt = (r+20)*(t-2)
rt = rt -2r + 20t - 40
2r - 20t + 40 = 0
r - 10t + 20 = 0
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t = 150/r
r - 1500/r + 20 = 0
r^2 + 20r - 1500 = 0
(r+50)*(r-30) = 0
r = 30 mph (Ignore the negative answer)
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