<PRE><B>Question 180502</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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Steve DATA:
distance = 150 miles ; rate = x mph ; time = d/r = 150/x hrs
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Improved Steve DATA:
distance = 150 miles : rate = x+20 ph ; time = d/r = 150/(x+2) hrs
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Equations:
Old Steve time - Improved Steve time = 2 hrs
150/x - 150/(x+2) = 2

150(x+2) - 150x = 2x(x+2)
300 = 2(x^2+2x)
x^2 + 2x - 150 = 0

x = [-2 +- sqrt(4 - 4*1*-150)]/2

x = [-2 +- sqrt(604)]/2
Positive  solution:

x = 11.29 mph (Old rate)
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Cheers,
Stan H.
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