How Is the Second Leg of the Triangle Calculated in Vector Problem?

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The resultant vector calculated is -6360, representing the distance a traveler must cover to return to the starting point. The angle was determined using the triangular sum theorem applied to a right triangle derived from a scalene triangle with sides measuring 6360, 2700, and 3660. There is a question regarding the origin of the value 3660. One participant suggests that the second leg of the triangle could be calculated as 45 x 60 x 1.5. The discussion focuses on clarifying the calculations involved in determining the triangle's dimensions and angles.
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Homework Statement
A student measures his own walking speed and discovers that it is 1.5 m/s. This student then plans a hike. He plans to start out by walking for 30 minutes due south at his usual constant speed. Then he will turn west slightly so that he is facing 35⁰ west of south, and he will walk (still at the same speed) for 45 minutes in that direction.

After he has completed this first 75 minutes of walking, If the student wants to walk back to where he started from, in what direction should he walk and how long will he need to walk for?
Relevant Equations
a^2 + b^2 = c^2
c^2 = sqrt{a^2+b^2-[2*a*b*cos(theta)]}
I tried finding the resultant vector which was -6360. The magnitude of -6360 is the distance the traveler must travel to reach the start.
I found the angle by using the triangular sum theorem on a right triangle that was split from a scalene triangle. The scalene triangle has side lengths of 6360, 2700, and 3660.
 
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Where did you get 3660 from?

I agree with the 2700. Wouldn’t the second leg of the triangle equal 45 x 60 x 1.5?
 
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