2. Welcome to Interactive Chalkboard Glencoe Geometry Interactive Chalkboard Copyright © by The McGraw-Hill Companies, Inc. Developed by FSCreations, Inc., Cincinnati, Ohio 45202 Send all inquiries to: GLENCOE DIVISION Glencoe/McGraw-Hill 8787 Orion Place Columbus, Ohio 43240

3. Splash Screen

4. Contents Lesson 7-1Geometric Mean Lesson 7-2The Pythagorean Theorem and Its Converse Lesson 7-3Special Right Triangles Lesson 7-4Trigonometry Lesson 7-5Angles of Elevation and Depression Lesson 7-6The Law of Sines Lesson 7-7The Law of Cosines

5. Lesson 4 Contents Example 1Find Sine, Cosine, and Tangent Ratios Example 2Evaluate Expressions Example 3Use Trigonometric Ratios to Find a Length Example 4Use Trigonometric Ratios to Find an Angle Measure

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

7. Example 4-1b

8. Example 4-1c

9. Example 4-1d

10. Example 4-1e Answer:

11. Example 4-1f Find sin A, cos A, tan A, sin B, cos B, and tan B. Express each ratio as a fraction and as a decimal.

12. Example 4-1g Answer:

13. Example 4-2a Use a calculator to find tan to the nearest ten thousandth. KEYSTROKES: 56 1.482560969 TANENTER Answer:

14. Example 4-2b KEYSTROKES: 90 0 COSENTER Answer: Use a calculator to find tan to the nearest ten thousandth.

15. a. Use a calculator to find sin 48° to the nearest ten thousandth. b. Use a calculator to find cos 85° to the nearest ten thousandth. Example 4-2c Answer:

16. End of Lesson 4

17. Transparency 4 Click the mouse button or press the Space Bar to display the answers.

18. Transparency 4a

19. End of Custom Show End of Custom Shows WARNING! Do Not Remove This slide is intentionally blank and is set to auto-advance to end custom shows and return to the main presentation.

20. End of Slide Show