1. Angle Relationships & Parallel Lines
Pre-Algebra

2. Complementary Angles sum to 90°
50°
40°

3. Complementary angles add up to 90º.
30º
40º
50º
60º
Adjacent and Complementary Angles
Complementary Angles but not Adjacent

4. Supplementary Angles sum to 180°
150°
30°

5. Supplementary angles add up to 180º.
40º
120º
60º
140º
Adjacent and Supplementary Angles
Supplementary Angles but not Adjacent

6. Practice Time!

7. 1) Find the missing angle.?°
36°

8. 1) Find the missing angle.?°
36°
90 ° – 36 = 54°

9. 2) Find the missing angle.?°
64°

10. 2) Find the missing angle.?°
64°
90 ° – 64° = 26°

11. 3) Solve for x.
2x°
3x°

12. 3) Solve for x.
2x°
3x°
3x° + 2x° = 90°
5x = 90
x =18

13. 4) Solve for x.
x + 25
2x + 5

14. 4) Solve for x. x + 25 2x + 5 (2x + 5) + (x + 25) = 90 3x + 30 = 90

15. 5) Find the missing angle.
168° ?°

16. 5) Find the missing angle.
168° ?°
180° – 168° = 12°

17. 6) Find the missing angle.?°
58°

18. 6) Find the missing angle.?°
58°
180° – 58° = 122°

19. 7) Solve for x. 5x 4x

20. 7) Solve for x. 5x 4x
4x + 5x = 180
9x = 180
x = 20

21. 8) Solve for x.
3x + 20
2x + 10

22. 8) Solve for x. 3x + 20 2x + 10 (2x + 10) + (3x + 20) = 180

23. The End