1. In Greek this just means: Working with Triangles
Trigonometry-2
In Greek this just means: Working with Triangles

2. Trigonometry
Hypotenuse, Opposite and Adjacent sides of right angled triangles.
Practise

3. Q P R Naming Triangle Sides
In trigonometry we work with right angled triangles.
To label a triangle we start by naming the corners or vertices.
Write any capital letter at each corner. P R
Mostly we label the corners A, B and C.

4. Q P R The Hypotenuse The hypotenuse is the longest side of a triangle.
It is always opposite the right angle.
Hypotenuse P R
In this example we are working with angle P.

5. Opposite Side Q
To find the side opposite the angle you are working with, put your finger on the angle. P R
Now move your finger through the triangle.
The side you get to is the opposite side.

6. Opposite Side Q
To find the side opposite the angle you are working with, put your finger on the angle. P R
Now move your finger through the triangle.
The side you get to is the opposite side.

7. Adjacent Side Q
The adjacent side starts from the point you are working with and goes to the right angle.
Opposite P R

8. Adjacent Side Q
The adjacent side starts from the point you are working with and goes to the right angle. P R

9. Adjacent Side Q
Now you know how to find the hypotenuse, opposite and adjacent sides of a right angled triangle.
Hypotenuse
Opposite P R
Adjacent
Remember:
It always depends on the angle you are working with.

10. N M O Label the Sides You are working with angle M.
Which side is the hypotenuse? M MN O MO NO

11. Label the Sides N
Hypotenuse M MN O MO
Well Done! NO

12. N M O Label the Sides You are working with angle M.
Which side is the opposite side? M MN O MO NO

13. Label the Sides N
Opposite M MN O MO
Well Done! NO

14. N M O Label the Sides You are working with angle M.
Which side is the adjacent side? M MN O MO NO

15. Label the Sides N
Hypotenuse
Opposite M MN O
Adjacent MO
Well Done! NO

16. N M O Label the Sides You are working with angle N.
Which side is the hypotenuse? M MN O MO NO

17. Label the Sides N
Hypotenuse M MN O MO
Well Done! NO

18. N M O Label the Sides You are working with angle N.
Which side is the opposite side? M MN O MO NO

19. Label the Sides N M MN O
Opposite MO
Well Done! NO

20. N M O Label the Sides You are working with angle N.
Which side is the adjacent side? M MN O MO NO

21. Label the Sides N
Hypotenuse
Adjacent M MN O
Opposite MO
Well Done! NO

22. A C B Label the Sides You are working with angle B.
Which side is the hypotenuse? A C AC AB BC B

23. A C B Label the Sides You are working with angle A.
Which side is the adjacent side? A C AC AB BC B

24. A C B Label the Sides You are working with angle B.
Which side is the opposite side? A C AC AB BC B

25. A C B Label the Sides You are working with angle B.
Which side is the adjacent side? A C AC AB BC B

26. A C B Label the Sides You are working with angle A.
Which side is the opposite side? A C AC AB BC B

27. Label the Sides N
Now you know how to label the sides of a right angled triangle.
Hypotenuse
Adjacent M MN O
Opposite MO NO

28. Well Done!

29. Oops!
Click to try again.