SOLUTION: two cyclists leave a city at the same time one going east and the other going west. the west bound cyclist bikes at 12 mph faster than the east bound cyclist. after 3 hours they ar

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Question 978858: two cyclists leave a city at the same time one going east and the other going west. the west bound cyclist bikes at 12 mph faster than the east bound cyclist. after 3 hours they are 126 miles apart. how fast is each cyclist riding?
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
Think of this as one cyclist standing still and
the other one biking at the sum of their speeds
until they are +126+ mi apart
Let +s+ = the speed of the slower cyclist in mi/hr
+s+%2B+12+ = the speed of the faster cyclist in mi/hr
----------------------------------------
+126+=+%28+s+%2B+s+%2B+12+%29%2A3+
+126+=+%28+2s+%2B+12+%29%2A3+
+126+=+6s+%2B+36+
+6s+=+90+
+s+=+15+
and
+s+%2B+12+=+27+
------------------
The east bound cyclist is going 15 mi/hr
The west bound cyclist is going 27 mi/hr
-------------
check:
e.b. cyclist:
+d%5B1%5D+=+15%2A3+
+d%5B1%5D+=+45+
------------
w.b. cyclist:
+d%5B2%5D+=+27%2A3+
+d%5B2%5D+=+81+
---------------
+d%5B1%5D+%2B+d%5B2%5D+=+45+%2B+81+
+d%5B1%5D+%2B+d%5B2%5D+=+126+
OK