I want to first say hello to everybody and thank you for this site because it is great and I have only been looking at it for about 2 hours. I need big time help in physics, but I am very interested in it so I guarantee I will be back very often and I hope it is not a problem to post/answer questions very often(adsbygoogle = window.adsbygoogle || []).push({});

1. The problem statement, all variables and given/known data

A jogger travels a route that has two parts. The first is a displacement A of 2.50 km due south and the second involves displacement B that points due east. A) The resultant displacement A + B has a magnitude of 3.75 km. What is the magnitude of B and what is the direction of A + B relative to due south? B) Supposed A-B had a magnitude of 3.75km. What then would be the magnitude of B and what is the direction of A-B?

2. Relevant equations

I made a force triangle of a south arrow A and east arrow B the resultant was drawn from the tail of A to the head of B.

A=2.50km S

B=??? E

Resultant = 3.75km

3. The attempt at a solution

I have found B which I got to be 2.80km/s E. using Pythagorean Theorem. A+B is in the direction of South East? This is where I get lost. I have no idea what subtracting vectors does to the direction or basically no idea on subtracting vectors at all. The magnitude of B would be the same though wouldn't it? So basically my question is am I on the right path and to help me find out what I am missing to this question like the direction of A-B. Thank you sooo much, plus any help on vectors would be awsome

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# Homework Help: First time posting Need extreme help on vectors!

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