Question

Vector Q is 0.321 m long in a

123° direction. Vector S is
0.876 m long in a -32.1°
direction.
Find the direction of their
vector sum.
direction (deg)

Answer 1

-19.09°.

Due to several approximations been applied in the detailed process, the angle given on image 2 (-18.17°) is slight minor compared to what can be obtained through direct calculations (-19.09°).

Check images below.

Note: If you want to calculate the length of the new vector, just need to apply the pythagorean theorem and taking the components of the result vector as if they were the 2 sides of a right triangle.