Geometry Unit 3: Parallel and Perpendicular Lines
Standards:
1. A-CED
2. G-CO 9: Prove geometric theorems.
a. Prove theorems about lines and angles. Theorems include: vertical angles are congruent; when a
transversal crosses parallel lines, alternate interior angles are congruent, corresponding angles
are congruent, points on a perpendicular bisector of a line segment are exactly those equidistant
from the segments endpoints.
3. G-CO 12: Make geometric constructions.
a. Make formal geometric constructions with a variety of tools and methods (compass and
straightedge, string, reflective devices, paper folding, dynamic geometric software, etc.).
Test Standards:
15. Identify parallel, skew, and perpendicular lines and give real-life examples of each.
16. Identify the angles created when a transversal cuts two parallel lines and identify the relationships
between those angles.
17. Use geometric constructions to demonstrate the parallel and perpendicular line postulates.
18. Identify and use the converse postulates and theorems to prove lines are parallel (Converse of the
Corresponding Angles Postulate, Converse of the Alternate Interior Angles Theorem, Converse of
Alternate Exterior Angles Theorem, Converse of Consecutive Interior Angles Theorem, and Parallel
Lines Property).
19. Compute slope of a line in the coordinate plane.
20. Identify the relationship between slopes of parallel and perpendicular lines.
21. Write equations of lines in slope-intercept form
22. Determine if lines are parallel, perpendicular, or neither from their equations.
23. Write equations in standard form.
24. Identify and use perpendicular transversals to prove lines parallel.
Test Standards:
15. Identify parallel, skew, and perpendicular lines and give real-life examples of each.
16. Identify the angles created when a transversal cuts two parallel lines and identify the relationships
between those angles.
17. Use geometric constructions to demonstrate the parallel and perpendicular line postulates.
18. Identify and use the converse postulates and theorems to prove lines are parallel (Converse of the
Corresponding Angles Postulate, Converse of the Alternate Interior Angles Theorem, Converse of
Alternate Exterior Angles Theorem, Converse of Consecutive Interior Angles Theorem, and Parallel
Lines Property).
19. Compute slope of a line in the coordinate plane.
20. Identify the relationship between slopes of parallel and perpendicular lines.
21. Write equations of lines in slope-intercept form
22. Determine if lines are parallel, perpendicular, or neither from their equations.
23. Write equations in standard form.
24. Identify and use perpendicular transversals to prove lines parallel.
Test Standards:
15. Identify parallel, skew, and perpendicular lines and give real-life examples of each.
16. Identify the angles created when a transversal cuts two parallel lines and identify the relationships
between those angles.
17. Use geometric constructions to demonstrate the parallel and perpendicular line postulates.
18. Identify and use the converse postulates and theorems to prove lines are parallel (Converse of the
Corresponding Angles Postulate, Converse of the Alternate Interior Angles Theorem, Converse of
Alternate Exterior Angles Theorem, Converse of Consecutive Interior Angles Theorem, and Parallel
Lines Property).
19. Compute slope of a line in the coordinate plane.
20. Identify the relationship between slopes of parallel and perpendicular lines.
21. Write equations of lines in slope-intercept form
22. Determine if lines are parallel, perpendicular, or neither from their equations.
23. Write equations in standard form.
24. Identify and use perpendicular transversals to prove lines parallel.
Test Standards:
15. Identify parallel, skew, and perpendicular lines and give real-life examples of each.
16. Identify the angles created when a transversal cuts two parallel lines and identify the relationships
between those angles.
17. Use geometric constructions to demonstrate the parallel and perpendicular line postulates.
18. Identify and use the converse postulates and theorems to prove lines are parallel (Converse of the
Corresponding Angles Postulate, Converse of the Alternate Interior Angles Theorem, Converse of
Alternate Exterior Angles Theorem, Converse of Consecutive Interior Angles Theorem, and Parallel
Lines Property).
19. Compute slope of a line in the coordinate plane.
20. Identify the relationship between slopes of parallel and perpendicular lines.
21. Write equations of lines in slope-intercept form
22. Determine if lines are parallel, perpendicular, or neither from their equations.
23. Write equations in standard form.
24. Identify and use perpendicular transversals to prove lines parallel.