Geometry A Unit 1

Question 1

betweenness of points

Answer 1

A condition of one point being between two other points on a line.

Question 2

bisector of a segment

Answer 2

A line or segment that intersects a segment at its midpoint.

Question 3

collinear points

Answer 3

Occurring on the same line.

Question 4

complement of a set

Answer 4

The elements in the universe that are not in the set.

Question 5

coplanar points

Answer 5

Occurring on the same plane.

Question 6

disjoint sets

Answer 6

Sets that have no common elements.

Question 7

element

Answer 7

An object that belongs to a set. Sometimes the word “member” is used.

Question 8

empty set

Answer 8

A set that has no elements. It is sometimes called the null set.

Question 9

finite set

Answer 9

Any set whose elements can be counted.

Question 10

geometry

Answer 10

From the Greek for “earth measure.”

Question 11

infinite set

Answer 11

Any set whose elements cannot be counted.

Question 12

intersection of sets

Answer 12

A set containing elements in common for all sets being considered.

Question 13

length of a segment

Answer 13

The distance between the endpoints of a segment.

Question 14

line segment

Answer 14

The set of two points and all points between.

Question 15

midpoint of a segment

Answer 15

A point that divides a segment into two equal segments.

Question 16

postulate

Answer 16

A statement accepted without proof.

Question 17

opposite rays

Answer 17

and are opposite rays if A, B, and C are collinear and B (the endpoint of both rays) is between A and C.

Question 18

proper subset

Answer 18

A subset that does not contain every element in another set.

Question 19

ray

Answer 19

A ray, , is the set of all points from point A infinitely in the direction of point B.

Question 20

set

Answer 20

A collection or group of objects.

Question 21

space

Answer 21

The set of all possible points.

Question 22

subset

Answer 22

A set that contains only elements found in another set.

Question 23

union of sets

Answer 23

A set containing all elements of all sets being considered.