May 12, 2015

Prove theorems about lines and angles. Theorems include: vertical angles are congruent; when a transversal crosses parallel lines, alternate interior angles are congruent and corresponding angles are congruent; points on a perpendicular bisector of a line segment are exactly those equidistant from the segment's endpoints.

Exercises from Illustrative Mathematics

A set of exercises, commentary, and solutions. For this unit, choose:

G-CO Points equidistant from two points in the plane

G-CO Congruent angles made by parallel lines and a transverse

- Mathematics > General
- Mathematics > Geometry

- Grade 9
- Grade 10

Reason abstractly and quantitatively.

Construct viable arguments and critique the reasoning of others.

Use appropriate tools strategically.

Attend to precision.

Look for and make use of structure.

Prove theorems about lines and angles.