Person A starts walking SW froma point at a speed of 13m/s. Ten seconds later person B starts walking from the same point and travels east at 10m/s. After person B have been walking 30 seconds, approximately how far apart are the two?

Answer 1

use the law of cosines

x^2 = (13*40)^2 + (10*30)^2 - 2(13*40)(10*30) cos 135°