Answer: y = 60x, choice D
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Step-by-step explanation:
1 hour = 60 miles ... one way to represent the speed of 60 mph
x hours = 60x miles ... multiply both sides by x
After x hours, the cheetah has ran 60x miles. This is assuming the speed is kept the same at 60 mph.
The information about the 50 yards is never used. It's likely thrown in there as filler or as a distraction.