Answer:
=135.53°
Step-by-step explanation:
The bearing that the captain should turn is the angle difference between the two islands from the position of the ship.
Let C be the position of the ship, then
AB is c=160
AC is b=220
BC is a=200
We use the cosine rule as follows:
c²=a²+b²-2ab Cos C
160²=200²+220²-2×200×220 Cos C
25600=88400-88000Cos C
88000 Cos C=88400-25600
88000Cos C=62800
Divide both sides by 88000.
Cos C=62800/88000
=0.7136
C=44.47°
He should turn (180°-44.47°)=135.53°
