CW#09
February 24, 2017
Quiz #8
1. What is the tangent of an acute angle in a right triangle?
2. Find x. a.
b.
•
•
•
•
what is the tangent ratio?
make a dot at the angel and label opposite, adjacent and hyp
write a proportion tan (<) / 1 = ...
cross multiply and divide
1
CW#09
February 24, 2017
Day / Date
Due Now
Warm­Up
Classwork Due: EOP
Homework Due: 2/27
LearningTarget
News and Notes
•
•
•
•
•
Friday, February 24
A#8: p. 469: #3 – 11, 16 – 26, 31, 32
Finish Quiz #8
CW#9: 7.6 p. 473 A#9: p. 477: #3 – 15, 18 – 27, 33, 34 Use the Sine and Cosine Ratios to Find Side Lengths in Right Triangles
Ch. 7 Test 3/6! No Talking
No phones
Stick to your own tests
can't share calcs
Good luck!
2
CW#09
February 24, 2017
3
CW#09
February 24, 2017
4
CW#09
February 24, 2017
5
CW#09
February 24, 2017
Geometry Questions 7.6
1. What is a sine ratio? The cosine ratio? How do we remember the ratios for sine, cosine, and tangent?
SOHCAHTOA!!
Example. Find the Sin (S) and Cos (S).
Then find Sin (R) and Cos (R).
6
CW#09
February 24, 2017
Practice. Find Sin (J) and Cos (J). Then find
Sin (K) and Cos (K).
7
CW#09
February 24, 2017
2. How do you use the sine and cosine ratios to find the missing side length in right triangle?
Set up an equation and solve!
Hint: use proportions! Cross-multiply and divide!
•
•
•
•
make a dot at your angle
label all sides opposite, adjacent, and hypotenuse
make a proportion...let tangent over 1 be the other fraction
cross-multiply and divide...is your answer reasonable?
Examples. Find x.
soh cah toa
16
x
22
34o
25o
x
8
CW#09
February 24, 2017
Practice. Find x.
x
32
37o
x
63
o
9
9
CW#09
February 24, 2017
3. What is the angle of elevation? The angle of depression? How do we use them to solve problems?
Angle of elevation: The measure of the
angle up from a horizontal plane (ground).
Angle of depression: The measure of the
angle down from a horizontal plane (air).
line of sight
We can use the angles to find angles in a
right triangle. Then set up an equation based
on SOHCAHTOA and solve!
Example.
10
CW#09
February 24, 2017
Practice. An airplane is descending into
SeaTac at an angle of depression of 12o. If
the distance on the ground from the plane to
the airport is 4.3 miles, how far will the plane
fly in the air to get to the airport? Draw a
picture!!
11
CW#09
February 24, 2017
A#9: p. 477: #3 – 15, 18 – 27, 33, 34
12
CW#09
February 24, 2017
Quiz #9
1. What does SohCahToa stand for?
2. You are standing on a cliff 100 feet above the ocean. You see a ship on the horizon. If your angle of depression is 22o, how long is your line of sight? How far is the ship from the base of the cliff? You will need to draw a picture!!! 13
Attachments
GraphPaper20x20AxesUnits.bmp