Problem 3-9 - Vector sum - (c)

Find the magnitude and direction of the sum of the vectors $A + B + C$ using the component technique. Assume two significant digits.
$A = 20\; km$ north, $B = 30\; km$ east, $C = 50\; km\; 55 ^\circ$ west of north.

This is certainly permissible but is counter-intuitive for people living in the northern hemisphere. We usually think of $\text{N} \rightarrow y$ and $\text{E}$ is to the right, i.e., $x$.
 
 

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