Question 1017876
9.  If Martin swims due north at 2mph and a current of 5mph is flowing due east, how fast does Martin swim and in what direction does he travel?
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It's a right triangle.
The legs are 2 & 5.  The hypotenuse is his speed wrt the Earth
= {{{sqrt(2^2 + 5^2) = sqrt(29)}}} mi/hr
=~ 5.385 mi/hr
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His direction (using 360 degs as North) is atan(5/2)
=~ 68.2 degs