1. Triangles

2. Can be classified by the number of congruent sides
Triangles
Can be classified by the number of congruent sides

3. Scalene Triangle
Has no congruent sides

4. Has at least two congruent sides
Isosceles Triangle
Has at least two congruent sides

5. Has three congruent sides
Equilateral Triangle
Has three congruent sides

6. Can be classified by the angle measures.
Triangles
Can be classified by the angle measures.

7. Right Triangle
Has one right angle

8. Acute Triangle
Has three acute angles

9. Triangle with one obtuse angle
Obtuse Triangle
Triangle with one obtuse angle

10. The sum of the angles of a triangle is 180 degrees.
Triangles
The sum of the angles of a triangle is 180 degrees.

11. To find a missing angle, add up the 2 given angles.
Triangles
To find a missing angle, add up the 2 given angles.

12. Subtract the sum from 180 and you have the missing angle.
Triangles
Subtract the sum from 180 and you have the missing angle.

13. Classify by the sides and angles.
Classify the Triangle
Classify by the sides and angles.

14. Classify the Triangle According to Sides and Angles

15. Classify by the sides and angles.
Classify the Triangle
Classify by the sides and angles.

16. Classify by the sides and angles.
Classify the Triangle
Classify by the sides and angles.

17. Classify by the sides and angles.
Classify the Triangle
Classify by the sides and angles.

18. Classify by the sides and angles.
Classify the Triangle
Classify by the sides and angles.

19. Classify by the sides and angles.
Classify the Triangle
Classify by the sides and angles.

20. Classify by the sides and angles.
Classify the Triangle
Classify by the sides and angles. 1 3 2

21. Classify by the sides and angles.
Classify the Triangle
Classify by the sides and angles.

22. Classify by the sides and angles.
Classify the Triangle
Classify by the sides and angles.

23. Find the measure of the missing angle
x = 180
x = 180
x = 59 x

24. Find the measure of the missing anglex 90
= 135
180 – 135 = 45 x

25. Find the measure of the missing angle
= 120
180 – 120 = 60 90 x x

26. Find the measure of the missing angle
2x+2x+2x = 180
6x = 180
X = 30
Each angle
measures 60˚ 2x 6 6 2x 2x

27. Find the measure of the missing angle
x+2x+3x = 180
6x = 180
x = 30˚
2x= 60˚
3x= 90˚ 2x 3x x

28. Find the measure of the missing angle
x+x+80 = 180
2x + 80 = 180
2x = 100
x = 50˚ 80