1. Trigonometry Ratios

2. Trigonometric Functions
We will be looking at 3 “trig” functions Sine (sin) Cosine (cos) Tangent (tan) The following ratios only apply in a right triangle.

3. SOHCAHTOA

4. sohcahtoa 13 5 12

5. sohcahtoa 17 8 15

6. What can I do with SOHCAHTOA?
We use these trig ratios to find missing parts of triangular relationships. We will learn to find missing side lengths today and missing angles next time.

7. Calculator Reminder!!!
Since our angles are being measured in degrees, always be sure to put your calculator in degree mode.
Press MODE button
3 setting down – degrees not radians

8. Finding sides in a Right Triangle:
Step 1: Set up the trig ratio:
Sin 35 =

9. Finding sides in a Right Triangle:
Step 2: Turn the ratio into a proportion:

10. Finding sides in a Right Triangle:
Step 3: Cross Multiply and solve for x.

11. Example:
Solve for x.

12. Example:
Solve for x.

13. Example:
Solve for x.

14. Example:
Solve for x.