G.2 types of triangle and angles of triangles
- 1. Types of Triangle and Angles of Triangles Classification and Properties
- 2. Types of Triangles Classification by Angles: ______________- the largest angle in the triangle is 90 ______________- the largest angle in the triangle is less than 90 ______________- the largest angle in the triangle is greater than 90 ______________- All three angles are congruent
- 3. Types of Triangles Classification by Sides: _______________: No sides have equal measure _______________: At least two sides have equal measure _______________: All three sides have equal measure
- 4. Group Poster Activity: Each member of your group should take one or two cards colored triangle cards and measure any missing angles and any missing sides with your protractor or ruler on your formula chart. Classify each triangle by sides and ALSO by angles, and paste on a poster like the demonstration on the white board Any section on your poster that does not have a picture, you and your group members should discuss if the picture can be drawn. If so, draw it on the poster, if not, write “ IS NOT POSSIBLE” in that section of your poster. 15 minutes for this activity, and then you will have to divide responsibilities for homework so poster is completed by next class
- 5. Special Triangle Theorems Related to ANGLES!!! ___________________________: The sum of the measures of ALL the angles in a triangle is 180 ___________________________: The measure of ONE exterior angle of a triangle will be equal to the sum of the measures of the two non-adjacent interior angles, These angles are sometimes called remote interior angles. ___________________________: When two angles of a triangle are congruent then the sides opposite those angles are congruent, THE CONVERSE IS ALSO TRUE!
- 6. DEMONSTRATION: Sum of Interior Angles of a Triangle Theorem
- 7. Remote Interior Angle Theorem Example: 80 60 140 x
- 8. Isosceles Triangle Theorem Example: 54 x
- 9. Homework Examples: (6y 20)° (8y + 6)° 8y°
- 10. Homework Examples (5x 8)° (4x + 20)°
- 11. HOMEWORK EXAMPLES: y° (4y 22)° 60°
- 12. Homework Examples: 132° (3x + 2)° (2x 7)°