Download 8-5 Angles of Elevation and Depression 2-23

2/23/2016
Five-Minute Check (over Lesson 8–4)
CCSS
Then/Now
New Vocabulary
Example 1: Angle of Elevation
Example 2: Angle of Depression
Example 3: Use Two Angles of Elevation or Depression
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Over Lesson 8–4
Use a calculator to find tan 54°.
Find m∠
∠B to the nearest tenth of a degree if
cos B = 0.8926 and ∠B is an acute angle.
(3-4) Find x. Round to the nearest tenth.
Use a special right triangle to express sin 45°as
a fraction.
Over Lesson 8–4
Use a calculator to find tan 54°.
A. 0.6738
B. 0.7432
C. 0.8090
D. 1.3764
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Over Lesson 8–4
Find m∠
∠B to the nearest tenth of a degree if
cos B = 0.8926 and ∠B is an acute angle.
A. 63.2
B. 26.8
C. 18.4
D. 0.999
Over Lesson 8–4
Find x. Round to the
nearest tenth.
A. 14.1
B. 17.4
C. 19.4
D. 21.3
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Over Lesson 8–4
Find x. Round to the
nearest tenth.
A. 9.5
B. 15.9
C. 23.7
D. 30.8
Over Lesson 8–4
Find x. Round to the
nearest tenth.
A. 34.7
B. 43.8
C. 46.2
D. 52.5
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Over Lesson 8–4
Use a special right triangle to express sin 45°as
a fraction.
A.
B.
C.
D.
Content Standards
G.SRT.8 Use trigonometric ratios and the
Pythagorean Theorem to solve right triangles
in applied problems.
Mathematical Practices
4 Model with mathematics.
1 Make sense of problems and persevere in
solving them.
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You used similar triangles to measure
distances indirectly.
• Solve problems involving angles of elevation
and depression.
• Use angles of elevation and depression to
find the distance between two objects.
• angle of elevation
• angle of depression
ɵ
Angle of elevation
ɵ
Angle of depression
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Angle of Elevation
CIRCUS ACTS At the circus, a person in the
audience at ground level watches the high-wire
routine. A 5-foot-6-inch tall acrobat is standing on
a platform that is 25 feet off the ground. How far is
the audience member (nearest tenth) from the
base of the platform, if the angle of elevation from
the audience member’s line of sight to the top of
the acrobat is 27°?
tan =
25 + 5.5
30.5
=
≈ 59.9
tan 27
tan 27 =
DIVING At a diving competition, a 6-foot-tall diver
stands atop the 32-foot platform. The front edge of
the platform projects 5 feet beyond the ends of the
pool. The pool itself is 50 feet in length. A camera is
set up at the opposite end of the pool even with the
pool’s edge. If the camera is angled so that its line of
sight extends to the top of the diver’s head, what is
the camera’s angle of elevation to the nearest
degree?
A. 37°
B. 35°
C. 40°
D. 50°
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Angle of Depression
DISTANCE Maria is at the top of a cliff and sees a
seal in the water. If the cliff is 40 feet above the
water and the angle of depression is 52°, what is
the horizontal distance from the seal to the cliff, to
the nearest foot?
Notice: ∠ ≅ ∠! by AIAT
tan =
40
40
=
≈ 31
tan 52
tan 52 =
Kathy is in a hot air balloon 30 feet above the
ground. She sees the landing spot at an angle of
depression of 34°°. What is the horizontal distance
between the hot air balloon and the landing spot to
the nearest foot?
A. 19 ft
B. 20 ft
C. 44 ft
D. 58 ft
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