Answer:
it obeys the law of vector addition
Explanation:
In the analytical method, we use the Pythagorean theorem to find the magnitude of the resultant because it obeys the law of vector addition.
The resultant of two vectors A and B is given by;
R' = A' + B'
[tex]R = \sqrt{A^2 + B^2}[/tex]
Therefore, Pythagorean theorem is used if the two quantities are vectors and vector quantities obey the law of vector addition.