Math 2 ____________Unit 1: Triangles Pt 1

Remind: text @18math2s to 81010Day Date Lesson Assignment Stamp

1 SyllabusTriangle Sum Theorem

2 Triangle Sum Theorem

3 Exterior Angle Theorem

4 Practice/Review

5 Quiz on Day 1-3Proof Notecards

6 Notecards

7 Notecards

8 Notecard Quiz

9 Parallel Lines

10 Parallel Lines

11 Parallel Lines

12 Quiz on Parallel Lines

13 Review

14 Unit 1 Test

1

Math 2 – Unit 1: Triangles Day 1: Triangle Sum Theorem

Parts of a Triangle:

Triangle – _______________________________________

Name – _______________

Sides – _______________

Vertices – _______________

Angles – _______________

Angle Sum Theorem:

The sum of the measures of the interior angles of a ___________________ is __________.

Example 1: Solve for the measure of the missing angle

You Try #1: Solve for the missing angle in each of the following triangles

a. b. c.

2

Vertical Angles Linear Pairs

Definition

Picture

Rule

Examples with Vertical AnglesExample 2: Solve for the measure of angles 1, 2, and 3 You Try 2: Solve for the measure of angles 1, 2, and 3

Examples with Linear PairsExample 3: Find the measure of Angle A You Try 3: Find the measure of Angle DCB

m∠ A = m∠DCB =

3

CA

B

D

20

56 2755B

D

C

A

In Class Practice

1. 2.

3. 4.

5. 6.

4

Unit 1 Day 1 Homework – Triangle Sum Theorem

1.

2.3.

b = ____________ b = ____________ x = ___________

4. 5. 6.

X = ___________ x = ___________ x = ____________

7. 8. 9.

? = __________ ? = _________ ? = ____________

5

Math 2 – Unit 1: TrianglesDay 2: Triangle Sum Theorem continued

You will need to be able to apply algebra skills to solve for missing angles

Example 1:

You Try 1: a. b. c.

Example 2: Use vertical angles to solve for the variable

6

You Try 2: Use vertical angles to solve for the variablea. b.

Example 3: Use linear pairs to solve for the variable

You Try 3: Use linear pairs to solve for the variablea. b.

7

Day 2 Homework – Triangle Sum Theorem Cont. Name:____________________1. 2.

3. 4.

5. 6.

7. NCFE Prep Question

The measure of Angle A is three times the measure of Angle B. The measure of Angle C is 8 less than the measure of Angle B. Find the measures of Angles A, B, and C.

8

Day 3 Exterior Angle Theorem

Find the measure of each angle1. 2.

3. 4.

5. 6.

9

Day 3 Exterior Angle Theorem

Find the measure of each angle x.7. 8.

9. 10.

11. 12.

10

Day 4 Practice!

Problem #1

Find m3 if m5 = 130 and m4 = 70.

Problem #2

Find m1 if m5 = 142 and m4 = 65.

Problem #3

Find m2 if m3 = 125 and m4 = 23.

Problem #4

m6 + m7 + m8 = _______.

Problem #5

If m6 = x, m7 = x – 20, and m11 = 80, then x = _____.

Problem #6

If m8 = 4x, m7 = 30, and m9 = 6x -20, then x = _____.

11

425

3 1

9

11

107

8

6

425

3 1

425

3 1

9

11

107

8

6

9

11

107

8

6

Problem #7Solve for x

.

Problem #8Solve for x

Problem #9Solve for x

Problem #10Solve for x

Problem #11 Find m1, m2, m3, m4, and m5.

12

x°

(5x)°120

35°

x° 140°

(4x)°

(3x + 54)ºx°

(x - 20)°

(2x)º

x°

34

52

1 142°

82°65°

46°

Day 5-8 Notecard Proofs

13

D is the midpoint of BC

DB C AC

AC ≅TR

BA CD

E

DEbisects AC

1 2

21

Day 9-12 Parallel LinesParallel Lines cut by a Transversal

Refer to the above figure and identify the special angle pair name.

1) 3 and 13 ______________________________________________________

2) 16 and 10 _____________________________________________________

3) 11 and 15 ____________________________________________________

14

13

16 1514

12 118 7

43

10965

21

M

L

N

PM⃗Pbisects∠LMNL

M

NJ K

JK⊥ LM

C and D are right angles.

T R

Q

P

∠1≅∠2∧∠2≅∠3

4) 8 and 6 ____________________________________________________

5) 1 and 6 _____________________________________________________

6) 6 and 10 _____________________________________________________

7) 14 and 15 _____________________________________________________

8) 7 and 12 _____________________________________________________

Let m1 = 115 and m12 = 110

13. m9 = ______ 14. m4 = ______

15. m10 = ______ 16. m11 = ______

17. m8 = ______ 18. m5 = ______

19. m3 = ______ 20. m14 = ______

Parallel Lines

Classify each pair of angles as alternate interior angles, same –side interior angles, or corresponding angles.

1. 2. 3.

4. 5. 6.

Use the figure to the right to answer questions 7, 8, and 9.

15

161514131211109

87654321

7. Name all of the pairs of corresponding angles in the picture.

8. Name all of the pairs of alternate interior angles in the picture.

9. Name all of the pairs of side-side interior angles in the picture.

Classify the relationship between each given pair of angles as alternate interior, alternate exterior, corresponding, or consecutive interior angles.

10. ∡4 ≅∡5

11. ∡5≅∡11

12. ∡4 ≅∡6

13. ∡7≅∡9

14. ∡2≅∡8

15. ∡3≅∡6

16. ∡1≅∡9

17. ∡3≅∡9

18. ∡6≅∡12

19. ∡7≅∡11

Parallel LinesFind the measure of the indicated angle.

20. 21.

22. 23.

16

24. 25.

26. 27.

17

Parallel LinesExample 1:

Example 2:

Example 3: You Try 1:

You Try 2: You Try 3:

18

4. 5.

6. 7.

8. 9.

19

10. 11.

12. 13.

20