Transcript Slide 1

Sine Tangent
Cosine
Hypotenuse
Why do we use
three figures
for bearings?
Two ships leave a port
at 13:00.
Ship A travels on a
bearing of 075° at a
speed of 12 km/h
Ship B travels on a
bearing of 110° at a
speed of 30 km/h.
1. Find y
5 cm
120°
7 cm
y
3. Find y
2. Find y
50°
y
60°
8 cm
9 cm
10 cm
y
11 cm
Learn the sine rule
a = b = c
sin A sin B sin C
and cosine rule
2
a = b2 + c2 – 2bc cosA
a) How far apart are
the ships at 15:30?
b) What is the bearing
of ship A from ship
B?