A man walks 8km north and then 5km in a direction 60o east of north. Find the distance from his starting point
-
A.
11.36km -
B.
12.36km -
C.
13.00km -
D.
14.36km
Correct Answer: Option A
Explanation
R = (sqrt {5^2 + 8^2 – 2 times 5 times 8 times cos 120^o})
R = (sqrt{129})
= 11.36km