A boy running in a northern direction later changes direction and started moving towards the Eastern direaction. If the distance he covered in the northern direaction 5km and in the Eastern direaction is 4km,determine a; the magnitude of his resultant.b; it's direaction

2 answers

"towards" the Eastern direction? Why not just say East?
√(5^2 + 4^2) = √41 km @ NθE where
tanθ = 4/5
d = sqrt(25+16) = sqrt(41) = 6.4 approximately
tan angle north of east = 5/4
so angle = 51.3 degrees N of E
Which is 90 - 51.3 = 38.7deg E of N or compass bearing of boy from start