Identify the side by Trig

Focus: review the use of sin, cos, and tan ratios

(sohcahtoa)

sohcahtoa

Identify the side that is opposite angle YZX

Z

X

Y

Line segment XYIs opposite angle Z

Hint: Identify the hypotenuse first

that eliminates one possibility

sohcahtoa

Identify the side that is adjacent to angle YZX

Z

X

Y

Line segment XZIs adjacent to angle Z

sohcahtoa

Identify the sides that are adjacent to AND opposite angle IHU

U

I

H

Line segment IHIs adjacent to angle IHU

Line segment IUIs opposite to angle IHU

hypotenuse

sohcahtoa

How long…1. …is the side opposite

angle ACB?

2. … is the hypotenuse?

3. What is the sin of angle ACB?

4. How long is the side adjacent to angle ACB?

5. What is cos of angle ACB?

A

BC

15 units

12 units

9 units

Sin= 12/15 = .8000

Opposite of ACB is linesegment AB – 12 units

hypotenuse is linesegment AC – 15 units

Cos= 9/15 = .6000

sohcahtoa

How long…1. …is the side opposite

angle 1?

2. … is the hypotenuse?

3. What is the sin of angle 1?

4. How long is the side adjacent to angle 1?

5. What is cos of angle 1?

x

Y

Z

24 units25 u

nits

7 units

Sin= 24/25 = .9600

Opposite of angle 1 is 24 units

hypotenuse is linesegment AC

25 units

Cos= 7/25 = .2800

sohcahtoa

What is…1. the cos of angle 2?

2. the sin of angle 2?

3. the tan of angle 2?

hm

i

8 units

6 units

10 units

Cos= 8/10 = .8000

Sin= 6/10 = .6000

Tan= 6/8 = .7500

Use your Chart for the next two slides

PAGE 668

sohcahtoa

Solve for x.

8.7071

h

8 units

X units

8sin 45

h

.7071 8

1 h

(8 1) .7071h

8 .7071

.7071 .7071

h

11.31units

sohcahtoa

What is the measure of side BT(the 52 degree angle)?

52 degree sin .7880

52 degree cos     .6157

52 degree tan 1.2799   r

b

t

18 units

x units

Tan 52= x/18

1.2799 = x/18

x =xxx units