1. Classification of Triangles

2. Table of Contents  Objective Objective  Review Review  Definition of a Triangle  Samples of Triangular Objects  Types of angles  Congruence of Line Segments  According to Angle Measure According to Angle Measure  According to Length of sides According to Length of sides  Review Questions Review Questions

3. Objective: AAAAt the end of the lesson, the students should be able to classify triangles.

5. Triangle It is a three sided polygon. A BC AC AB BC

6. Samples of Triangles that can be seen around us.

8. Acute Angle -It is an angle whose measure is less than 90 0. 30 0 A B C <BAC which is an acute angle.

9. Right Angle -It is an angle whose measure is equal to 900. 90 0

10. Obtuse Angle - It is an angle whose measure is greater than 90 0 but less than 180 0. 150 0

11. How can we say that two segments are Congruent ?

12. *Two segments are congruent if and only if they have equal length. C D 10 cm measure of AB = measure of CD A B

13. CLASSIFICATION OF TRIANGLES According to angles According to sides

15. 60 0 48 O *ACUTE TRIANGLE -All the angles of the triangle are acute. J L K 72 0 <J,<K,<L are all acute angles.

16. RIGHT TRIANGLE -An angle in a triangle is a right angle. 90 0 M O N <M is a right angle. leg The side opposite the right angle of a right triangle is called the hypotenuse. The other sides are called legs. HYPOTENUSE

17. OBTUSE TRIANGLE - An angle in a triangle is an obtuse angle. P Q 128 0 <P is an obtuse angle. R

19. SCALENE TRIANGLE -No two sides are congruent. A B AB =BC = CA AB = BC = CA 4 cm 6 cm C 9 cm ~~

20. D F ISOSCELES TRIANGLE -two sides of the are congruent. E DE = FE base leg leg The two equal sides of an isosceles triangle are called legs. The third side is called the base. ~

21. EQUILATERAL TRIANGLE -Three sides are congruent. G I H GH = HI = GI ~~

22. R e p o r t e d t o : S a l v a d o r S a l a z a r R e p o r t e d b y : J e r e m y J a v i e r Mr. THE END!!!