1. 5.1 Solving Right Triangles

2. * remember the opposite & adjacent sides change with
Back in Geometry we learned SOH–CAH–TOA!
It was to remember 3 trig functions in a right triangle θ c
= hyp
opp = a b
= adj
* remember the opposite & adjacent sides change with
respect to where the angle θ is

3. Some basic solving: Ex 1) Solve for a and c. c a (Degree mode!) B 42°20

4. angle of angle of elevation depression
* Most of these situations are in the context of a word problem!
JUST DRAW A PICTURE!
Ex 2) A security camera in a bank mounted on a wall 10 feet from the floor is aimed at a spot on the floor 22 feet away. Determine the angle of depression.
angle of depression
angle of angle of
elevation depression
line of sight
angle of elevation
(they are the same! alternate
interior angles) θ 10 θ 22

5. Ex 3) The length of a parallel of latitude can be found by
R = radius of Earth (6400 km)
B = degree latitude
Determine the length of the 29th parallel
= 35, 171 km

6. Ex 4) A surveyor observes that the top of a building makes an angle of 37.2° with the road. From another location 400 ft away the angle of elevation is 20°. How far is the base of the building from the first observation point on the road?
Do 2 right △s!
Solve for h first h h
20°
37.2°
400 x
Store  H
= ft

7. Homework
#501 Pg #13, 15, 17, 21, 23, 25, 28, 31, 33, 36, 37, 39, 41, 43