1. Bell Work: List 3 triangle congruence theorems
If two triangles are congruent, what can you conclude about their angles?
When are two hexagons congruent? (How many conditions must the two hexagons satisfy?)

2. 4.5: Isosceles and Equilateral Triangles

3. Notes An Isosceles triangle is a triangle that has two congruent sides
The Legs of an isosceles triangle are the two congruent sides, and the base is the side between them.
The legs of an isosceles triangle form the vertex angle between them
The remaining two angles are the base angles

5. Partner Work What are the base angles of the large triangle?
What conclusion can you draw about the large triangle?
Is AB congruent to CB? Justify
Is Angle A equal to Angle DEA? Justify

6. If I construct an Isosceles Triangle with a line bisecting the vertex angle(as shown to the right), what is true of the two triangles formed?

8. What is the value of x?
What relationship do AD and DC have?

10. In b., what other conclusions can we draw about the sides or angles of the triangle?

11. Find m and n

12. 4.6: Congruence in Right Triangles(HL Method)

13. Notes
A triangle is called a right triangle if there is one right angle in the triangle
In a right triangle, the side opposite the right angle is called the hypotenuse. The Hypotenuse is always the longest side in the triangle
The other sides are referred to as legs

15. Conditions for using the HL Theorem
1. The triangles must be right triangles
2. Both triangles must have congruent hypotenuses
3. Both triangles must have one pair of congruent legs

16. Find x and y such that the triangles are congruent by HL

19. Homework
4.5, page 254, 256: 6-9, 14, 16, 17, 30
Honors: Add 15, 20
4.6, page :1-7, 9, 12, 25
Honors: Add 19-22
Quiz on Thursday!

20. 4.5
Find M and N

21. 4.6