Bearings question : what am I doing wrong?

[M_BONG]

Hi everyone,

I was attempting an exercise of Vectors (bearing) in Maths Quest. Had an issue with drawing diagrams.

The first question was "A plane is travelling 300km east, then 300 km north. Show resultant bearing is 67.5 degrees N"
(Diagram as below)/

The second question was "A plane is travelling 400km west, then 600km north, find bearing"
(Diagram as below).

My question is, why is the first question's diagram drawn as a non-right angle triangle? Ie. 300km north was not taken as due north. Yet, in the second question, "then 600km north" is assumed to be due north? (Ie. a right angle triangle is drawn).


 Can someone explain please!! Thanks!  Please tell me if you did not understand my question!

[mackintosh]

Hi everyone,

I was attempting an exercise of Vectors (bearing) in Maths Quest. Had an issue with drawing diagrams.

The first question was "A plane is travelling 300km east, then 300 km north. Show resultant bearing is 67.5 degrees N"
(Diagram as below)/

The second question was "A plane is travelling 400km west, then 600km north, find bearing"
(Diagram as below).

My question is, why is the first question's diagram drawn as a non-right angle triangle? Ie. 300km north was not taken as due north. Yet, in the second question, "then 600km north" is assumed to be due north? (Ie. a right angle triangle is drawn).


 Can someone explain please!! Thanks!  Please tell me if you did not understand my question!

This diagram would be valid if the '600km north' statement instead read '600km north east', a typo perhaps? 45deg to horizontal is not north, I agree.

[M_BONG]

This diagram would be valid if the '600km north' statement instead read '600km north east', a typo perhaps? 45deg to horizontal is not north, I agree.

So you're saying, if an object is said to be moving "north" (or any other direction like west) you assume it is travelling due north/west?

[mackintosh]

No sorry , I think that there is a typo in the question

[Apink]

The first question was "A plane is travelling 300km east, then 300 km north. Show resultant bearing is 67.5 degrees N"

It's just a typo in the question. It should be "A plane is travelling 300km east, then 300 km north-east. Show resultant bearing is 67.5 degrees N"