1. Lesson 9-1 & 9-2: Trigonometry of Right Triangles (Sine, Cosine, Tangent)
SOH-CAH-TOA

2. Using Trigonometry in Right Triangles
Be able to find the ________, ________, and __________ sides from an angle
__________ & _________ depend on where you start!
Adjacent means “______”
Hypotenuse ______ hypotenuse
Opposite
Adjacent
Hypotenuse
Adjacent
________
Hypotenuse
Hypotenuse
Opposite
________
Opposite
_______
________
Adjacent
Opposite
Adjacent
Next to
STAYS

3. Trig Ratios
Use _________, _________, and ____________ to set up ratios (fractions)
These ratios are related to the size of the__________
Three Trig Functions
Opposite
Adjacent
Hypotenuse
Angle
Sine (sin)
____________
Find them on your
calculator!
Cosine (cos)
Tangent (tan)
Sin, cos, tan are _________ talking about an angle!!!
ALWAYS

4. Trig Ratios A
300 2 B C 1
SOH-CAH-TOA
► ____________

5. Using calculator to find angles
From the previous slide, solve for angle A:
So:
Inverse of sin is sin-1
angle
fraction/decimal
Sin of an ___________ gives the ___________________
fraction/decimal
angle
Sin-1 of an ____________________ gives the ___________

6. Using Trig Finding a missing side
Label the angle, given side, and ___________ side (x)
Draw a _____________ by the angle
Identify the given and missing sides using ___________, ______________, and _________________
Choose 1 of the 3 equations from: _________________
Fill in equation with numbers and x
Solve using a __________ (sin, cos, tan can be over “1”)
Finding a missing angle given 2 sides
Follow steps 1 – 5 above, then
Solve for the angle by using the __________ trig function with the fraction/decimal →
missing
stick figure
adjacent
opposite
hypotenuse
SOH-CAH-TOA
proportion
inverse

7. Find sin L, cos L, tan L, sin N, cos N, and tan N
Find sin L, cos L, tan L, sin N, cos N, and tan N. Express each ratio as a fraction and as a decimal.
Example 4-1a

8. Answer:
Example 4-1e

9. EXERCISING A fitness trainer sets the incline on a treadmill to The walking surface is 5 feet long. Approximately how many inches did the trainer raise the end of the treadmill from the floor?
Let y be the height of the treadmill from the floor in inches. The length of the treadmill is 5 feet, or 60 inches.
Example 4-3a

10. Proportion: Multiply sin 70 by 60, divide by 1 if you want to
KEYSTROKES:
SIN
ENTER X
Answer: The treadmill is about 7.3 inches high.
Example 4-3b