Geomentry Vocabulary

Point

0 dimensions (no length, no area, no volume)

Line segment

1 dimension (finite length, no area, no volume)

Line

1 dimension (infinite length, no area, no volume)

Ray

1 dimension (infinite length, no area, no volume)

Plane

2 dimensional (infinite length, infinite area, no volume)

Circle

A geometric figure that is made up of an infinite number of points equidistant from one specific point called the center.

Angle

A measurement of two rays or line segments joining at single point.

Reflex angle

An angle that is greater than 180 degrees but less than 360

Obtuse angle

An angle that is more than 90 degrees but less than 180 degrees

Acute angle

Angle less than 90 degrees

Complementary angles

Angles that add up to 90 degrees

Congruent angles

Angles that are mathematically equal

Parallel

Lines that don't intersect

Perpendicular

Lines that intersect at 90 degrees

Polygon

Many-sided (at least 3 sides, closed, sides are line segments, has area, interior angles do not have to have the same measure, and angles don't have to be the same length.)

Equidistant

Points are the same distance from each point

Reflexive

a ∼ a

Straight angle

an angle that is exactly 180 degrees

Right angle

angle exactly 90 degrees

Equiangular

angles are the same distance

supplementary angles

angles that add up to 180 degrees

Vertical angles

angles that are opposite from each other when there's an intersection is congruent

Transitive

if a∼b, and b∼c, then a∼c

Symmetric

if a∼b, then b∼a

Angle bisector

line/point that cuts an angle in half

Midpoint

point in the middle

coplanar

points on the same plane

Collinear

points that are on the same line

Regular polygon

same distance from each point and center

Equilateral

sides are the same length