1. 8.1 Building Blocks of Geometry
6.4.2 I can describe figures by using the terms of geometry

2. Vocabulary
point
line
plane
line segment
ray

5. Use the diagram to name the geometric figure.
A. three points V S U W T
B. two lines

6. A. three different line segments
Use the diagram to give a possible name to the figure.
A. three different line segments C A B
B. three ways to name the line

7. Lesson Quiz
Use the diagram to name each geometric figure.
1. three points
2. two lines
3. a point shared by a line and a ray
4. a plane
Possible answer: A, B, C
Possible answer: AD, CE
Possible answer: F
Possible answer: plane AEC

8. 8.2 Measuring and Classifying Angles
I can name, measure, draw, and classify angles

9. Vocabulary angle vertex acute angle right angle obtuse angle
straight angle

10. An acute angle measures greater than 0° and less than 90°.
A right angle measures exactly 90°.
Right angles are usually marked with a symbol.
Reading Math

11. An obtuse angle measures greater than 90° and less than 180°.
A straight angle measures exactly 180°.

12. Additional Example 3: Classifying Angles
Classify each angle as acute, right, obtuse, or straight.
A. B.
The angle measures less than 90°, so it is an acute angle.
The angle measures exactly 90°, so it is a right angle.

13. The angle measures less than 90°, so it is an acute angle.
Check It Out: Example 3
Classify each angle as acute, right, obtuse, or straight.
A. B.
The angle measures less than 90°, so it is an acute angle.
The angle measures exactly 180°, so it is a straight angle.