arbitrary line from the point of depression

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Angles of Elevation and
Depression
• Sometimes drawing a diagram of the situation
described in a problem can help you to solve
problems involving angles of elevation and
depression. Angles of elevation or depression to
two different objects can be used to find the
distance between those objects.
Angles of Elevation and Depression
• The following is a pictorial example of angles of
elevation and depression:
This is the angle of depression
This is the angle of elevation
Arbitrary line from the point of depression
• If an arbitrary line is drawn from the point of depression,
we can assume that the line is parallel to the ground. If
it is parallel to the ground, then the angle of depression
is ________________ to the angle of elevation.
x 
arbitrary line from the point of depression
x 
Example: Name the angles of elevation and
depression in each figure:
 of elevation: _______
 of elevation: _______
of depression: _______
of depression: _______
 of elevation: _______
of depression: _______
 of elevation: _______
of depression: _______
Examples:
You can use Trigonometric ratios to
find the angles of elevation and depression.
1.
Hanna is on the Observation Deck of the John Hancock Center on the 94th
floor, which is 1030 feet above the ground. Arnold is on the Skydeck of the
Sears Tower on the 103rd floor, which is 1335 feet from the ground. The
John Hancock Center is 1.7 miles or 8976 feet from the Sears Tower. To the
nearest tenth, what is the angle of elevation from Hanna to Arnold?
2. A surveyor is 130 feet from a tower.
The tower is 86 feet high. The
surveyor’s instrument is 4.75 feet above the ground. Find the angle
of elevation, to the nearest degree.
3. A ski slope is 550 yards long with a vertical drop of 130 yards. To
the nearest tenth of a degree, find the angle of depression of the
slope.
4. Jordan is 50 feet from the tallest totem pole. The tallest totem pole, located
in Canada, is 173 feet high. If Jordan’s eyes are 5 feet from the ground, find
the angle (to the nearest tenth) of elevation for her line of sight to the top of
the totem pole.
5. Dustin is visiting the Blue Ridge Parkway outside Floyd, Virginia. The angle
of elevation for his line of sight to the top of the Blue Ridge Parkway
Welcome Sign is 75. If his line of sight is 6 feet from the ground and the
sign is attached to the pole 110 feet above the ground, how far is he from the
base of the pole, to the nearest foot?
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