Question 472836
Two motorcycles made the same 315 mile drive. One motorcycle traveled 10 mph faster than the other and arrived 2 hours earlier. Find the speed of each motorcycle.
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315/r = 315/(r+10) + 2
315(r+10) = 315r + 2r(r+10)
315r + 3150 = 315r + 2r^2 + 20r
2r^2 + 20r - 3150 = 0
r^2 + 10r - 1575 = 0
(r + 45)*(r - 35) = 0
r = 35 mph slower
r = 45 mph faster