1. lesson 40.notebook January 15, 2013
Assignment:
1­­>Set 40 (evens) ­ Due Tomorrow [1/16]

2. lesson 40.notebook January 15, 2013
Lesson 40 Warm­Up:
Simplify:
1) 5/8 + 3/4 + 1/2
2) 3/10 ­ (1/2 ­ 1/5)
3) 8 1/3 x 1 4/5
4) 5 5/6 7
5) 7 5 5/6

3. lesson 40.notebook January 15, 2013
Lesson 40:
*Take your triangle and "rip off" each angle:
Then...line up each of the "angles" and tell me what you find!
SO....the sum of the measures of the angles of a triangle:
180 degrees

4. lesson 40.notebook January 15, 2013
Angle Pairs:
2 1
3 4
*Angles 1 and 2 are adjacent angles ­ they share a common side
(So are 2 and 3; 3 and 4; 1 and 4)
*Angles 1 and 2 are also supplementary ­ they total 180 degrees
(So are 2 and 3; 3 and 4; 1 and 4)
*Angles 1 and 3 are vertical angles ­ they are a pair of nonadjacent angles that are
formed by intersecting lines
(Angles 2 and 4 are too!)
***Complementary angles ­ are 2 angles whose sum is 90 degrees!

5. lesson 40.notebook January 15, 2013
Examples (Lesson 40):
A) If the sides of a "regular" triangle are equal in length and the
angles are equal in measure, then what is the measure of each angle?
60 degrees

6. lesson 40.notebook January 15, 2013
Use the figure below to answer the following questions.
D A
70
C B
B) What is the measure of <ACB and why?
C) What is the measure of <CAB and why?
D) Are angles ACD and CAB vertical angles? Why or why not?

7. lesson 40.notebook January 15, 2013
E) Find the measures of x, y, and z in this figure.
80
y
40 x
z
m x =
m y =
m z =