A football player runs the pattern given in the drawing by the three displacement vectors A, B, and C. The magnitudes of these vectors are A = 5.0 m, B= 15 m, and C = 18 m. Using the component method, find the magnitude and direction è of the resultant vector

Answer 1

You have made this problem impossible by the most fundamental error.
You gave us scalars, not vectors!
Vectors have both magnitude (scalar length) and DIRECTION !!!
Without direction, the three "things" are simply not vectors and they certainly do not have components.