This slide show was prepared to help my fourth grade students understand and identify the different types of triangles and to help them with their homework.

1. TOPIC 9 LESSON 9-5 Triangles

2. Triangles can be classified by their sides. 3 equal sides equilateral triangle

3. Triangles can be classified by their sides. 2 equal sides isosceles triangle

4. Triangles can be classified by their sides. 0 equal sides scalene triangle

5. Triangles can also be classified by their angles. 1 right angle right triangle One angle measures 90 degrees. The other 2 are acute or less than 90 degrees.

6. Triangles can also be classified by their angles. 3 acute angles acute triangle All angles measure less than 90 degrees.

7. Triangles can also be classified by their angles. 1 obtuse angle obtuse triangle One angle measures greater than 90 degrees.

8. Classify this triangle by its sides and angles.

9. Did you say. . . equilateral, acute? 3 equal sides, 3 acute angles

10. Classify this triangle by its sides and angles.

11. Did you say . . . isosceles, right? 2 equal sides, one right angle

12. Classify this triangle by its sides and angles.

13. Did you say . . . scalene, obtuse? 0 equal sides, 1 obtuse angle

14. Can you classify this triangle by its sides and angles?

15. Did you say . . . scalene, right? 0 equal sides,1 right angle

16. Classify this triangle by its sides and angles.

17. Did you say. . . isosceles, acute 2 equal sides, 3 acute angles

18. Now you know how to identify triangles.