1. Agenda 2/25/13 1) Bell Work 2) Outcomes
3)Finish Solving Right Triangle Notes(9.6)
4) Review quiz concepts
5) Problem Packet(possibly group work)
tablet password = cosine

2. Bell Work 2/27/13 1)Use Pythagorean Theorem 2) Use Special Right
x = _____ y = _____ a = _____ b = ____
3) Solve for the missing side using Trig Ratios
A) B)
w = _____ x = _____

3. Outcomes I will be able to:
1) Use Properties of special right triangles
2) Understand Trigonometric Ratios
3) Use Pythagorean Theorem
4) Understand proportions in triangles

4. 9.6 Notes – Solving Right Triangles
What does it mean to solve a right triangle?
Solve a Right Triangle – Determine the measures of all six parts of a right triangle (3 angles and 3 sides).
You can solve a right triangle if you know:
1. Two side lengths
2. One side length and one acute angle measure

5. Inverses 1. If sin A = x, then _________________.
2. If cos A = y, then _________________.
3. If tan A = z, then _________________.
***You can use either your calculator or your trig table to determine the angle measure.

6. Examples Use a calculator or trig ratio table to find the following.
1. Sin A = Cos B = .1392
3. Tan C = Cos A = .9659

7. Examples
5. Solve the right triangle. Round decimals to the nearest tenth.
What trig ratios do we have to determine angle A and C?
From A: Cos A = 8/10 = .8
From C: Sin C = 8/10 = .8
Look at trig table to determine the angle measures
Angle A = 36°
Angle C = 54° 8 10 A B C

8. Examples
6. Solve the right triangle. Round decimals to the nearest tenth.
What trig ratios do we have?
Looking at a
Sin 65 = a/20
Convert Sin 65 to decimal using chart
.9063 = a/20
x x 20
18.1 = a
Cos 65 = b/20 – repeat the process
.4226 = b/20
8.5 = b a
65º 20 x Y Z b

9. Examples
7. Solve the right triangle. Round decimals to the nearest tenth.
What trig ratios do we have?
Cos 20 = y/15
.9397 = y/15
14.1 = y
Sin 20 = x/15
.3420 = x/15
5.1 = x T S R 15
20º x y

10. Examples 1 1.8 What is the height of the balloon? Tan 28° = h/1.8
8. During a hot air balloon flight, Willie and Nia look upwards and see the balloon, as shown in the diagram below. The angle of elevation from Nia is 28˚ and she is 1.8 miles from the spot on the ground directly below the balloon.
What is the height of the balloon?
Tan 28° = h/1.8
h = .96
Willie is 2.8 miles from Nia.
Find the angle of elevation from Willie.
Tan W = .96/1
m ∠W = 44° W N h
28° 1
1.8