# Geometry Vocab

## 29 terms · Study for the quiz tomorrow!

### point

no dimension; represented by a point

### line

one dimension; represented by line with two arrowheads

### plane

flat surface made up of points that extend in all directions. One plane through any 3 points not on the same line.

### definition

explained using undefined terms

### collinear

points that lie in the same plane.

### coplanar

points that lie in the same plane

### line segment

can be measured because it has endpoints.

### congruent segments

segments that have the same measure

### midpoint

the point halfway between the endpoints of the segment

### bisects

the action of any segment, line, or plane that intersects a segment at its midpoint

### undefined terms

only explained using examples and descriptions

### defined terms

explained using only undefined terms and/or other defined terms

### locus

set of points that satisfy a particular condition

### betweenness of points

for any two real numbers a and b, real number n is between a and b, so a < n < b

### constructions

methods of creating geometric figures without the benefit of measuring tools

### distance

the length between two points as the endpoints
AB = (square root) (x2-x1)^2 + (y2-y1)^2

### irrational numbers

cannot be written as a quotient of two integers

### ray

part of a line; one endpoint and extends indefinitely in one direction

### opposite rays

two rays that share a common endpoint and go in opposite directions

### angle

formed by two noncollinear rays that havea common endpoint

### sides

the rays are called _____ of an angle

common endpoint

### interior

inside of an angle

### exterior

outside of an angle

### degree

results from dividing the distance around a circle into 360 parts

90 degree angle

### acute angle

less than 90 degrees

### obtuse angle

more than 90 degrees

### angle bisector

a ray that divides an angle into two congruent angles