Objectives:
1. To solve right
triangles
2. To solve problems
using directional
bearings
•
•
•
•
•
•
•
Assignment:
P. 359: 1-10 S, 13
P. 359: 15-21 S
P. 359-360: 22-28 S
P. 360-361: 29-36 S
P. 361: 37-40 S
P. 363: 63 c & d
HW Supplement: 1
You will be able
to solve right
triangles
When confronting a
triangular problem in
trigonometry, we usually
abide by the convention
that all right triangles are
called 𝐴𝐵𝐶, where ∠𝐶 is
the right angle and 𝑐 is the
hypotenuse.
Side a
Opposite
A
Side b
B
Side c
C
If the legs of a right triangle are 3 and 4, what is
the measure of the angle opposite the
smallest side?
To solve a right triangle means to find all of its
sides and angles. Using trigonometry, what
must you know to solve a right triangle?
Solve the right triangle.
Round your answers
to the nearest tenth.
You will be able
to solve
problems using
directional
bearings
Getting lost was pretty easy to
do in the days before your
phone told you exactly
where you were and where
you needed to go.
Navigators in those ancient
days got around by finding
their bearings.
An aeronautical bearing is the clockwise
direction between two points A and B
measured in degrees relative to a North-South
line (meridian).
Meridian
Fancy way of writing 71°
“North “ can refer
to either magnetic
north or true north
Navigators always
use 3 digits when
measuring a
bearing so that
35° is never
confused with
350°.
Navigators always
use 3 digits when
measuring a
bearing so that
35° is never
confused with
350°.
To distinguish
themselves from
pilots, sailors insist on
using a different type
of bearing. A nautical
bearing is an acute
angle measured in
degrees from North or
South, towards either
East or West.
To distinguish
themselves from
pilots, sailors insist on
using a different type
of bearing. A nautical
bearing is an acute
angle measured in
degrees from North or
South, towards either
East or West.
Convert the following aeronautical bearings into
nautical bearings.
1. 035
2. 140
3. 260
4. 301
Convert the following nautical bearings into
aeronautical bearings.
1. N 15 E
2. N 15 W
3. S 15 E
4. S 15 W
What is the bearing from B back to A?
A sailboat leaves its pier at a bearing of 270 at 8
knots (nautical miles per hour). After 15
minutes, the boat changes course to a bearing
of 344 at 10 knots. Find the sailboat’s bearing
and distance from the pier after 12 minutes
on this course.
Armed with a compass and an odometer, you
set off on a bike trail consisting of two legs.
The first leg takes you 20 miles at a bearing of
050, while on the second leg, you ride 12
miles at a bearing of 125. What is the
distance, as the crow flies, from the starting
point to your destination? What is the
bearing?
Objectives:
1. To solve right
triangles
2. To solve problems
using directional
bearings
•
•
•
•
•
•
•
Assignment:
P. 359: 1-10 S, 13
P. 359: 15-21 S
P. 359-360: 22-28 S
P. 360-361: 29-36 S
P. 361: 37-40 S
P. 363: 63 c & d
HW Supplement: 1