## Symbol Toolbox

- Line, ray, line segment

- Angle with vertex

or - Distance between and

- Measure of

- Perpendicular

= - Equal

- Congruent

*Markings*

## Keywords, Postulates, and Theorems

**Points, Lines, and Planes**

- Geometry
- Point
- Line
- Plane
- Space
- Collinear
- Coplanar
- Endpoint
- Line Segment
- Ray
- Intersection
- Postulates
- Theorem
- Postulate 1-1
- Postulate 1-2
- Postulate 1-3
- Postulate 1-4
- Postulate 1-5

**Segments and Distance**

- Distance
- Measure
- Ruler Postulate
- Segment Addition Postulate

**Angles and Measurement**

- Angle
- Vertex
- Sides
- Protractor Postulate
- Straight Angle
- Right Angle
- Acute Angles
- Obtuse Angles
- Convex
- Concave
- Polygon
- Perpendicular
- Construction
- Compass
- Angle Addition Postulate

**Midpoints and Bisectors**

- Congruent
- Midpoint.
- Midpoint Postulate
- Segment Bisector
- Perpendicular Bisector
- Perpendicular Bisector Postulate
- Angle Bisector
- Angle Bisector Postulate

**Angle Pairs**

- Complementary
- Supplementary
- Adjacent Angles
- Linear Pair
- Linear Pair Postulate
- Vertical Angles
- Vertical Angles Theorem

**Classifying Polygons**

- Triangle
- Right Triangle
- Obtuse Triangle
- Acute Triangle
- Equiangular Triangle
- Scalene Triangle
- Isosceles Triangle
- Equilateral Triangle
- Vertices
- Diagonals

## Review

Match the definition or description with the correct word.

- When three points lie on the same line. — A. Measure
- All vertical angles are ________. — B. Congruent
- Linear pairs add up to _______. — C. Angle Bisector
- The in from of . — D. Ray
- What you use to measure an angle. — E. Collinear
- When two sides of a triangle are congruent. — F. Perpendicular
- — G. Line
- A line that passes through the midpoint of another line. — H. Protractor
- An angle that is greater than . — I. Segment Addition Postulate
- The intersection of two planes is a ___________. — J. Obtuse
- — K. Point
- An exact location in space. — L.
- A sunbeam, for example. — M. Isosceles
- Every angle has exactly one. — N. Pentagon
- A closed figure with 5 sides. — O. Hexagon

P. Bisector

## Texas Instruments Resources

*In the CK-12 Texas Instruments Geometry FlexBook, there are graphing calculator activities designed to supplement the objectives for some of the lessons in this chapter. See http://www.ck12.org/flexr/chapter/9686.*