1. Solve for the unknown:

2. Section 9-1: Solving Right Triangles Objective: To use trigonometry to find unknown sides or angles of a right triangle. Learn and remember triangle and angle vocabulary

3. Types of triangles Scalene Isosceles Equilateral Right

4. Types of triangles Scalene Isosceles Equilateral Right

5. Types of angle Right Acute Obtuse

7. vocabulary Vertex… vertices Pythagorean theorem Hypotenuse

8. These are the general formulas you will need in order to find any unknown angle or side in a right triangle.

9. Labeling format

10. To Solve a triangle To solve a triangle means to find the value of ALL angles and sides.

11. Example: Solve the triangle below:

12. Solution: To find the value of b, use either tan 28 ⁰ Using tan 28 ⁰ :Using sin 28 ⁰ to find C B=B=

13. Example: continued solutions: B=62 o b=75.2 c=85.2

14. Angles of Elevation and Depression The angle of elevation of an object as seen by an observer is the angle between the horizontal and the line from the object to the observer's eye (the line of sight).

15. Angles of Elevation and Depression If the object is below the level of the observer, then the angle between the horizontal and the observer's line of sight is called the angle of depression.

18. Parallel lines – equal angles A A A A B B B B

19. Alternate interior angles are congruent A A A A B B B B

20. Vertical angles are congruent A A A A B B B B

21. Corresponding angles are congruent A A A A B B B B

22. Parallel lines – supplementary angles A A A A B B B B

23. A A A A B B B B

24. Linear pairs are supplementary A A A A B B B B

25. Same-side-interior angles are supplementary A A A A B B B B

26. SEE ATTACHED WORKSHEET FOR PRACTICE PROBLEMS