Trigonometry

1
Trigonometry

• Introduction to Trigonometry

2
Review of Triangles

• Labeling Triangles
• Vertices
• Sides

A
b
c
C
B
a
3
Review of Triangles

• Sum of Angles

?A ?B ?C 180?
A
C
B
4
Review of Triangles

• Sum of Angles

?A ?B ?C 180?
A
?A ? ? 180?
??
??
?A 180? - 70? - 33?
?A 77?
77?
70?
70?
33?
33?
C
B
5
Types of Triangles

• Scalene
• Isosceles
• Equilateral
• Right

6
Scalene Triangle
7
Isosceles Triangle
Sides Opposite the Base Angles are Equal
Base Angles are Equal
8
Example
5.8 cm
x
5.8 cm
79?
65?
65?
180? - 22?
158?
158?
79?
2
9
Equilateral Triangles
10
Example
60?
x
y
60?
4.5
11
Altitudes
vertex
opposite side
12
Altitudes in Isosceles Triangles
100?
50?
50?
18
9
9
13
Altitudes in Equilateral Triangles
??
? ft
25 ft
14
Right Triangles
hypotenuse
leg
90?
leg
15
Pythagorean Theorem
hypotenuse
c
leg
a
leg
b
16
Pythagorean Theorem

• Is this a right triangle?

5.4 cm
1.9 cm
4.9 cm
NO 29.16 isnt equal to 27.62
17
Pythagorean Theorem
8 ft
8
6 ft
6
?
18
Example
1.2
4.4
x
19
Pythagorean Theorem
28 ft
28
?
45
45 ft
20
Example
x
13 cm
32 cm
21
Practice Set 1

• Pages 6 8 1 -14 all