1. 2.7 – Triangles

2. Type of ∆DefinitionPicture Equilateral Triangle CLASSIFICATION BY SIDES All sides are ≅

3. Type of ∆DefinitionPicture Isosceles Triangle CLASSIFICATION BY SIDES 2 Sides ≅ base leg

4. Type of ∆DefinitionPicture Scalene Triangle CLASSIFICATION BY SIDES No sides are ≅

5. Type of ∆DefinitionPicture Equiangular Triangle CLASSIFICATION BY ANGLES All angles are ≅

6. Type of ∆DefinitionPicture Acute Triangle CLASSIFICATION BY ANGLES All angles are acute

7. Type of ∆DefinitionPicture Right Triangle CLASSIFICATION BY ANGLES One right angle leg hypotenuse

8. Type of ∆DefinitionPicture Obtuse Triangle CLASSIFICATION BY ANGLES One obtuse angle and 2 acute angles

9. Classify the triangle by the best definition based on sides and angles. Then find the sum of the interior angles.

10. scalene right

11. equilateral equiangular

12. isosceles obtuse

13. 4. The sum of ANY triangles interior angles is 180°. Use this fact to solve for x below.

14. x + 75 + 54 = 180 x + 129 = 180 x = 51

15. 2x + 3x + 55 = 180 5x + 55 = 180 x = 25 5x = 125

16. 4x – 1 + 3x + 90 = 180 7x + 89 = 180 x = 13 7x = 91

17. A = 30 un 2 A = ½(12)(5) A = 30 un 2 A = ½(12)(5) A = 30 un 2 A = ½(12)(5)

18. b h b h Triangle:

19. PicturePerimeterArea Triangle Add the 3 sides

23. 4. If the area of the triangle is 63cm 2, find the height of the triangle.