Pls help with a vector problem in physics?

Question

6. A barge is being towed north at the rate of 15 miles an hour. A man walks across the deck, from west to east, at the rate of 6 feet a second. Find the direction and the magnitude of his actual velocity.

Answer 1

15 mph = 22 f/s

c² = a² + b²

c = √(a² + b²)

c = √(22² + 6²)

c = √520

c = 22.8 f/s

tan(x) = 6/22

x = 15.827° NNE

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