Lesson 1: 1-4: Angle Measure

1. Why is the order of the letters important when you are naming a ray or an angle?
2. What are the parts of an angle?
3. How do you classify angles?

Ray
Opposite Rays
Angle
Side
Vertex
Interior
Exterior
Degree
Right Angle
Acute Angle
Obtuse Angle
Angle Bisector

G.CO.1
Know precise definitions of angle, circle, perpendicular line, parallel line, and line segment, based on the undefined notions of point, line, distance along a line, and distance around a circular arc.
G.CO.12
Make formal geometric constructions with a variety of tools and methods (compass and straightedge, string, reflective devices, paper folding, dynamic geometric software, etc.)

https://docs.google.com/document/d/1zq0M4k71wKerXCRC7RRT03j2PjfmBImlaTgUCbpHxkw/copy?usp=sharing

An angle is the intersection of two noncollinear rays at a common endpoint, called the vertex. Angles are measured in degrees and are classified by their measure. Angles that have the same measure are congruent. A ray that divides an angle into two congruent angles is called an angle bisector.

One of the skills Dale must learn in carpentry class is how to cut a miter joint. This joint is created when two boards are cut at an angle to each other. He has learned that one miscalculation in angle measure can result in mitered edges that do not fit together.

It is common for students to misread a protractor because the rays of the angle are misaligned. In order to read the angle measure directly from the protractor, one ray must be exactly aligned with the 0 line, not the bottom of the protractor.

Students approaching grade level can be given practice problems in small groups to work with other students or directly with the teacher.
Students beyond grade level can make deeper connections in the following way: students can work together to determine the three things that must be true of adjacent angles.

Formative Assessment

Textbook in class

Access online textbook and resources through class link.