1. Trigonometry-3 In Greek this just means: Working with Triangles

2. Trigonometry Working with Greek letters to show angles in right angled triangles. Exercises

3.  We often use Greek letters for angles.  One of the letters is called theta.  It is written as θ. Using Greek Letters for Angles θ θ stands for the size of the angle, e.g. 30°.

4.  One letter is: θ, called theta  Another letter is: β, called beta.  Another letter is: α, called alpha. Other Greek Letters for Angles These letters are all sometimes used in trigonometry.

5.  The hypotenuse is always the side opposite the right angle. The Hypotenuse θ Hypotenuse

6.  Move your finger onto angle θ. The Opposite Side of θ θ  Move your finger down the middle of the triangle.  The side you get to is the opposite side.

7. The Opposite Side of θ θ Opposite

8.  The adjacent side starts from the angle you are working with and goes to the right angle. Adjacent Side θ

9.  Now you know how to find the hypotenuse, opposite and adjacent sides of a right angled triangle. Adjacent Side Hypotenuse Opposite Adjacent θ

10.  You are working with angle θ.  Which side is the hypotenuse? Label the Sides a b c θ a b c

11. Hypotenuse a b c Well Done! θ a b c

12.  You are working with angle θ.  Which side is the opposite side? Label the Sides a b c θ a b c

13. a b c Well Done! Opposite θ a b c

14.  You are working with angle θ.  Which side is the adjacent side? Label the Sides a b c θ a b c

15. a b c Well Done! θ a b c Adjacent Hypotenuse Opposite

16.  You are working with angle θ.  Which side is the hypotenuse? Label the Sides a b c a b c θ

17. Hypotenuse a b c Well Done! a b c θ

18.  You are working with angle θ.  Which side is the opposite side? Label the Sides a b c a b c θ

19. a b c Well Done! Opposite a b c θ

20.  You are working with angle θ.  Which side is the adjacent side? Label the Sides a b c a b c θ

21. a b c Well Done! a b c θ Adjacent Hypotenuse Opposite

22.  Now you know how to label the sides of a right angled triangle. Label the Sides Hypotenuse a b c Opposite Adjacent a b c θ

23. Well Done!

24. Oops! Click to try again.