Transcript Answers to Homework

ANSWERS TO HOMEWORK
1) 14.4
5) 9.9
9) 37
13) 53
2) 73.8
6) 7.1
10) 34
14) 51
17) x = 101.8, y = 63.6
19) x = 27.4, y = 12.2
21) x = 13.7, y = 78
23) x = 88, y = 46
3) 16.7
7) 10.3
11) 23
15) 46
18)
20)
22)
24)
4) 26.0
8) 5.6
12) 38
16) 27
x = 26, y = 64
x = 11.8, y = 10.7
x = 7.1, y = 44
x = 18, y = 9.3
8-7 APPLICATIONS OF RIGHT
TRIANGLE TRIGONOMETRY
Answers to Warm Up
x
sin 56 
12
y
cos 56 
12
Equal
y
sin 34 
12
x
cos 34 
12
x Reciprocal
y
tan 56 
tan 34 
y
x
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
20
x  286m
x
4
TOO: DRAW A PICTURE AND SOLVE!
1)
Two buildings on opposite sides of the street are
40m apart. From the top of the taller building
the angle of depression to the top of the shorter
building is 13°. How much shorter is the
shorter building than the taller building?
9m
2)
A road 1.6km long rises 400m. What is the
angle of elevation? (Hint: 1000m = 1km)
14°
SECRET COMPARTMENTS
20
10
x
For
10
x:
x
Fill in
the sides
x
20
10
20
45
45
30
60
TRIANGLES
RIGHT
Solve
SECRET COMPARTMENTS
x
sin10 
20
x  3.5
20
cos10 
x
x  20.3
10
tan x 
20
x  27
45
45-45-90
30-60-90
x
x√2
45
x√3
x
60
30
2x
x
CHAPTER 8
Write
four
common triples
and
a
multiple
(x2)
What do
you use if
it’s not a
common
triple?
Your Name and Period
SECRET COMPARTMENTS
SECRET COMPARTMENTS
3,4,5
6,8,10
5,12,13 10,24,26
8,15,17 16,30,34
7,24,25 14,48,50
Pythagorean 2
2 + b2
c
=
a
Theorem
HOMEWORK
Page 318 #1-6
 Page 304 #1-7 (Self Test)
