Answer: All Real Numbers Are Solutions
Step-by-step explanation:
Given that,
A motor boat travels 60 miles down a river in 3 hours but takes 5 hours to return upstream,
We know that,
Speed = distance/time
The rate while moving downstream
The rate while moving upstream 
The rate of the boat in still water is the average of these:

The rate of the current is the difference between the boat speed and actual speed = 16 mph - 12 mph = 4 mph
Hence, this is the required solution.
Answer:
Check.
Step-by-step explanation:
To prove it we need to know that for two matrices A and B we have that:
det(AB) = det(A)*det(B) and
. Now:





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