1. Unit 5 – Geometry Basic Vocabulary
Lesson 1
Vocabulary

2. Unit 4 : Lesson 1 Definitions
1. Point: a specific location in space often represented by a dot.
Ex. point A A ∙

3. Unit 4 : Lesson 1 Definitions
2. Line: a set of points whose length goes on forever in 2 opposite directions.
Ex. Line AB and Line GH.

4. Unit 4 : Lesson 1 Definitions
3. Line segment: the part of a line between two points on a line. __
Ex. Line segment AB or AB.

5. Unit 4 : Lesson 1 Definitions
4. Endpoints: the points at the end of a line segment or a ray.
Ex. Point A and Point B are endpoints
for line segment AB.

6. Unit 4 : Lesson 1 Definitions
5. Ray: a part of a line that begins at an endpoint and goes on forever in one direction. →
Ex. Ray MN or MN.

7. Unit 4 : Lesson 1 Definitions
6. Angle: a figure formed by 2 distinct rays with a common endpoint called the vertex.
Ex. Angle BAC or CAB.

8. Unit 4 : Lesson 1 Definitions
7. Plane: a flat surface that has no edges or boundaries that goes on forever in all directions.
Ex. Plane ABCD.

9. Unit 4 : Lesson 1 Definitions
8. Intersection: the point at which two or more lines intersect or cross.
Ex. Line AE and Line CD intersect
at point B.

10. Unit 4 : Lesson 1 Definitions
9. Perpendicular lines: lines that meet to form right angles.
Ex. Line AB and Line CD are
perpendicular lines.

11. Unit 4 : Lesson 1 Definitions

12. Unit 4 : Lesson 1 Definitions
11. Bisector: a line or ray that divides a segment or angle into 2 equal parts.
Ex. Ray BR bisects Angle BCA

13. Unit 4 : Lesson 1 Definitions
12. Congruent: figures that have the same size, shape, and measure.
Ex. Angle RSW and Angle TSW
are congruent.