SOLUTION: Caitlin recently rode her bicycle to visit her friend who lives 12 miles away. On her way there, her average speed was 10 miles per hour faster than on her way home. If Caitlin spe
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-> SOLUTION: Caitlin recently rode her bicycle to visit her friend who lives 12 miles away. On her way there, her average speed was 10 miles per hour faster than on her way home. If Caitlin spe
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Question 1054732: Caitlin recently rode her bicycle to visit her friend who lives 12 miles away. On her way there, her average speed was 10 miles per hour faster than on her way home. If Caitlin spent a total of 1 hour bicycling, find the two rates. Answer by ewatrrr(24785) (Show Source):
You can put this solution on YOUR website! 12/r + 12/(r+10) = 1
Multiply thru by r(r+10)
12(r+10) + 12r = r(r+10)
12r + 120 + 12r = r^2 + 10r
r^2 - 14r - 120 = 0
(r + 6)(r-20) = 0
r = and r+10 =