SOLUTION: A man walks due west for 4km.He then changes direction and walks on a bearing of 197°until he is south-west of his starting point.How far is he then from his starting point?
Algebra ->
Customizable Word Problem Solvers
-> Travel
-> SOLUTION: A man walks due west for 4km.He then changes direction and walks on a bearing of 197°until he is south-west of his starting point.How far is he then from his starting point?
Log On
Question 1183252: A man walks due west for 4km.He then changes direction and walks on a bearing of 197°until he is south-west of his starting point.How far is he then from his starting point? Answer by Boreal(15235) (Show Source):
You can put this solution on YOUR website! Draw this:
This is an obtuse triangle with the first leg (west) 4 km
The second leg is unknown but the angle is 107 degrees, 90 for a track of 180 and 107 deg for a track of 197 deg.
The angle between where he started and the route back is 45 degrees, since he is southwest of where he started.
Use the law of Sines
sin 107/long side (answer)=sin 28/4 km
so long side=4*sin 107/sin 28
=8.15 km