Angle Relationships & Parallel Lines

1 / 41

# Angle Relationships & Parallel Lines - PowerPoint PPT Presentation

Angle Relationships & Parallel Lines. Pre-Algebra. Adjacent angles are “side by side” and share a common ray. 15 º. 45 º. These are examples of adjacent angles. 45 º. 80 º. 35 º. 55 º. 130 º. 50 º. 85 º. 20 º. These angles are NOT adjacent. 100 º. 50 º. 35 º. 35 º. 55 º. 45 º.

I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.

## Angle Relationships & Parallel Lines

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.

- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript

### Angle Relationships&Parallel Lines

Pre-Algebra

These are examples of adjacent angles.

45º

80º

35º

55º

130º

50º

85º

20º

100º

50º

35º

35º

55º

45º

Complementary angles add up to 90º.

30º

40º

50º

60º

Supplementary angles add up to 180º.

40º

120º

60º

140º

100°

100°

80°

80°

Lines l and m are parallel.l||m

Note the 4 angles that measure 120°.

120°

120°

l

120°

120°

m

Line n is a transversal.

n

Lines l and m are parallel.l||m

Note the 4 angles that measure 60°.

60°

60°

l

60°

60°

m

Line n is a transversal.

n

Lines l and m are parallel.l||m

There are 4 pairs of angles that are vertical.

There are many pairs of angles that are supplementary.

60°

120°

120°

60°

l

60°

120°

120°

60°

m

Line n is a transversal.

n

If two lines are intersected by a transversal and any of the angle pairs shown below are congruent, then the lines are parallel. This fact is used in the construction of parallel lines.

1) Find the missing angle.

36°

90 ° – 36 = 54°

2) Find the missing angle.

64°

90 ° – 64° = 26°

3) Solve for x.

2x°

3x°

3x° + 2x° = 90°

5x = 90

x =18

4) Solve for x.

x + 25

2x + 5

4) Solve for x.

x + 25

2x + 5

(2x + 5) + (x + 25) = 90

3x + 30 = 90

3x = 60

x = 20

5) Find the missing angle.

168°

180° – 168° = 12°

6) Find the missing angle.

58°

180° – 58° = 122°

7) Solve for x.

5x

4x

4x + 5x = 180

9x = 180

x = 20

8) Solve for x.

3x + 20

2x + 10

8) Solve for x.

3x + 20

2x + 10

(2x + 10) + (3x + 20) = 180

5x + 30 = 180

5x = 150

x = 30

11) Find the missing angles.

70 °

70 °

Hint: The 3 angles in a triangle sum to 180°.

d °

65 °

11) Find the missing angles.

70 °

70 °

40°

Hint: The 3 angles in a triangle sum to 180°.

75 °

65 °

12) Find the missing angles.

45 °

50 °

Hint: The 3 angles in a triangle sum to 180°.

d °

75 °

12) Find the missing angles.

45 °

50 °

85°

Hint: The 3 angles in a triangle sum to 180°.

20°

75 °

In the figure a || b.

13. Name the angles congruent to 3.

1, 5, 7

14. Name all the angles supplementary to 6.

1, 3, 5, 7

15. If m1 = 105° what is m3?

105°

16. If m5 = 120° what is m2?

60°