Download 8-4 ANGLES OF ELEVATION AND DEPRESSION

Geometry Warm ups
8-4 ANGLES OF ELEVATION
AND DEPRESSION
Essential Understanding
Describing angles
• What is the description of each angle as it relates to the
situation shown?
Example
• When the sun’s angle of elevation is 38°, a building
casts a shadow of 45m. How tall is the building?
x
tan 38 
45
x  35m
x
45
38
Example
• From the top of a lighthouse 20m tall, a sailboat is
sighted having an angle of depression of 4°. How
far from the lighthouse is the boat?
20
tan 4 
x
x  286m
20
4
x
Draw a picture and solve!
A library needs to build an access ramp for
wheelchairs. The main entrance to the library is 8 ft
above sidewalk level. If the architect designs the
slope of the ramp in such a way that the angle of
elevation is 5°, how long must the access ramp be?
Round your answer to the nearest tenth of a foot.
91.8 ft
TWAP or TOO
• A meteorologist measures the angle of elevation of
a weather balloon as 31. A radio signal from the
balloon indicates that it is 100 meters from his
location. To the nearest meter, how high above the
ground is the balloon?
•
(Draw your OWN picture and solve.)
52 m
Homework
• 8-4 Practice Worksheet